Quasi-3D Light Confinement in Double Photonic Crystal Reflectors VCSELs for CMOS-Compatible

Quasi-3D Light Con?nement in Double

Photonic Crystal Re?ectors VCSELs for

CMOS-Compatible Integration

Corrado Sciancalepore,Badhise Ben Bakir,Xavier Letartre,Jean-Marc Fedeli,Nicolas Olivier,Damien Bordel, Christian Seassal,Pedro Rojo-Romeo,Member,IEEE,Philippe Regreny,and Pierre Viktorovitch

Abstract—A novel architecture of one-dimensional photonic crystal membrane(PCM)re?ectors embodying a heterostructure is proposed as a robust design aimed at a3-D ef?cient con?ne-ment of light in single-mode polarization-controlled 1.55-m vertical-cavity surface-emitting laser(VCSEL)microsources for heterogeneous integration on complementary metal-oxide-semi-conductor(CMOS).On the basis of a theoretical approach,the paper focuses on the deep interweaving between the kinetics of light transport in the mirrors and the physical nature of the ex-ploited Fano resonances.An example of VCSEL design for optical pumping employing heterostructure-con?ned photonic crystal mirrors is presented.The predicted photons kinetics along with the considerable improvement in cavity modal features owing to the enhanced mirror architecture have been con?rmed by per-forming rigorous three-dimensional?nite-difference time-domain (3-D FDTD)calculations.Finally,experimental observations of photoluminescence(PL)emission performed on?rst-ever fabri-cated devices for optical pumping show striking agreement with theoretical considerations and ab initio modelling.

Index Terms—Photonic crystals,photons,semiconductor lasers, slow Bloch mode,vertical-cavity surface-emitting lasers(VC-SELs).

I.I NTRODUCTION

A CHIEVING a full control of photons in the

real—reciprocal space as well as in the frequency—time domain is decisive for the design of innovative optical components aimed at further breakthroughs in the?eld of micro-nano-photonics.An ef?cient harnessing of light is made possible by con?ning photons within the tiniest spatial domain (in comparison to the wavelength)for the longest time possible (as compared to the oscillation period),while allowing to be ef?ciently collected(from)or addressed(to)the photonic structures where are meant to be con?ned.

Manuscript received December22,2010;revised April19,2011,May05, 2011;accepted May10,2011.Date of publication May23,2011;date of current version June15,2011.This work was supported by the European Commission in the framework of the project HELIOS.

C.Sciancalepore is with the Institut des Nanotechnologies,Ecole Centrale de Lyon,F-69134Ecully,France(e-mail:corrado.sciancalepore@ec-lyon.fr) and with the Commissariatàl’énergie Atomique et auxénergies Alternatives, Département Optronique,(CEA-LETI Minatec),F-38054Grenoble,France (e-mail:corrado.sciancalepore@cea.fr).

X.Letartre,C.Seassal,P.Rojo-Romeo,P.Regreny,and P.Viktorovitch are with the Institut des Nanotechnologies,Ecole Centrale de Lyon,F-69134Ecully, France.

B.Ben Bakir,J.-M.Fedeli,N.Olivier,and D.Bordel are with the Commis-sariatàl’énergie Atomique et auxénergies Alternatives,Département Optron-ique,(CEA-LETI Minatec),F-38054Grenoble,France.

Digital Object Identi?er10.1109/JLT.2011.2157303

An effective control of light is highly desirable in the case of laser microcavities and devices for non-linear applications where the need for a stronger light-matter coupling is even more binding.This concept is particularly true in vertical-cavity sur-face-emitting lasers(VCSELs),where the coupling of the op-tical mode with the active material is crucial for low-threshold emitters and modal control constitutes an additional require-ment to be addressed especially for telecommunication-oriented applications.As widely proposed in the literature,while ver-tical con?nement is achieved through diffractive phenomena provided by distributed Bragg re?ectors(DBRs),the lateral op-tical waveguiding(or antiguiding)and modal behaviour in VC-SELs generally relies on a complex interplay of index-[1]and gain-guiding mechanisms[2].

Speci?cally,in arsenide lasers,the enhancement of the pho-tons-matter coupling along with modal selection was accom-plished by introducing an optimized transverse optical and elec-trical con?nement via oxide windows[3]–[7].However,the main drawback of such solutions lies with the ineludible de-sign trade-offs between single-mode operation,low threshold and optical output power[6].Using shallow surface reliefs[5] has only partly addressed the issue given the still considerable drop in emitted power;on the other hand,VCSELs’designs based on external cavity con?gurations and index antiguiding [7]for the suppression of higher order modes are characterized by rather complicated and possibly unstable processing.Con-cerning InP-based VCSELs,while ef?cient carrier funnelling has been obtained by means of structured[8]–[10]or proton-im-planted[11]tunnel junctions,this device class is still waiting for an ef?cient optical con?nement owing to the lack of index guiding[11].Solutions based on the incorporation of2-D pho-tonic crystals(PhCs)in proton-implanted devices[11]are af-fected by signi?cant drawbacks due to light leaking through the photonic crystal holes disrupting laser operation,even calling into question the actual feasibility of the fabrication process. In electro-thermally tunable micro-electro-mechanical sys-tems(MEMS)-VCSELs,curved micro-machined DBR mem-branes have been successfully employed in order to improve the transverse con?nement of the fundamental mode while main-taining a good modal selection[8].Nonetheless,these mirrors are affected by several important disadvantages such as the lack of lateral(typical diameters100m)and longitudinal(cavity physical length15m)compactness,tight epitaxial and fab-rication constraints.

Regarding polarization control,different strategies have been so far adopted in VCSELs:elasto-[12]and electro-optic[13], [14]induced birefringence,asymmetric cavity geometries[15]

0733-8724/$26.00?2011IEEE

Fig.1.Left:Exemplifying sketch of2.5-D PCM-VCSEL structures for op-tical pumping.Materials,refractive indices,and physical lengths are reported in Table I.Right:Top view of Si/SiO one-dimensional photonic crystal mir-rors.

and current injection[16],elliptical surface reliefs[17]as well as sub-wavelength gratings[18],[19].Nevertheless,although the latter solution provides a good polarization mode suppres-sion ratio(PMSR),a precise control over the grating etch depth and duty cycle is necessary to ensure a stable polarization. Since Yablonovitch’s paper in the late‘80s[20],photonic crystals were increasingly employed to control the spatial-tem-poral trajectory of photons through the diffractive con?nement arising from the high-index-contrast periodical structuring of the optical medium.In photonic crystal membranes(PCMs) [21]–[24],the control of light by diffractive phenomena is com-bined with the refractive con?nement arising from the index guiding provided by the strong contrast between the high-index slab core and the low-index cladding.In the past years,dif-ferent groups[24]–[30]suggested to shift from thicker,ef?-ciency-limited,narrow-bandwidth DBRs to PCMs as wideband polarization-sensitive re?ectors in VCSELs.Recently,high-nu-merical-aperture PCM mirrors enabling a double focusing for both re?ected and transmitted waves have been proposed as building block for a new class of VCSELs and solid-state lasers [31].

Although PhCs operating in the photonic bandgap regime have been already successfully employed in VCSELs[32],[33], however,PCMs working in the slow-light regime through the excitation of surface-addressable slow Bloch modes via low-Q Fano resonances(FRs)represent a very attractive solution as ef?cient compact mirrors.Fano resonances arise from the res-onant coupling between slow Bloch modes wave-guided in the PCM re?ector with the background radiation continuum.Spec-tral properties of the resonances and coupling strength depend on the parameters de?ning the membrane design such as dielec-tric constant corrugation,slab thickness and?lling factor. Another interpretation of the physics governing light in PCMs lies in the destructive(or constructive)interference between the modes propagating through the membrane[along -axis,see Fig.1(right)],which is set by the design,deter-mining the strong re?ective(transmissive)behavior of the membrane[34].

This innovative photonic architecture can accommodate in-plane wave-guided modes which are deliberately opened to the third spatial dimension by accurately tailoring the cou-pling with the radiation continuum.Hence,the optical modes supported by a VCSEL cavity employing double photonic crystal re?ectors are combination of a wave-guided(within the mirrors)and a radiated component(coupled to the active material in between the mirrors)giving origin to so-called hybrid modes.

TABLE I

M ATERIALS,R EFRACTIVE I NDICES,AND P HYSICAL L ENGTHS IN PCM-VCSEL

S Essentially,from2-D micro-nano-photonics,where only in-plane truly wave-guided modes are concerned,we are moving into the realm of2.5-D-photonics where a quasi-3D accurate light harnessing at the wavelength scale is made possible.As already demonstrated[26],one-dimensional broadband PCMs in VCSELs led to signi?cant improvements in terms of optical mode lateral con?nement,modal selection and polarization control.By exploiting two spectrally over-lapped low-Q Fano resonances,resulting in large stopbands up to150nm,such re?ectors opened new perspectives also for the design of electro-statically tunable single-mode polariza-tion-controlled laser microsources,thus gradually substituting DBRs as alternative competing mirrors.

Starting from a deeper theoretical understanding of photons kinetics in1-D PCMs,with the present paper we propose a novel PCM design embodying a photonic crystal heterostruc-ture aimed at a dramatic increase in the lateral con?nement in long-wavelength VCSELs meant for the III-V/Si integration on complementary metal-oxide-semiconductor(CMOS).This is achieved by reducing the lateral escape rate of photons out of the mirrors by means of energy barriers.

A photonic crystal heterostructure[35]–[40]consists in one photonic crystal(i.e.,the PCM re?ectors of our VCSEL)en-closed laterally between two adjacent different crystals.The two crystals are chosen in such a way that photons can propagate in the central layer—the pass-band well—while encountering a forbidden bandgap region in the side layers which forms the so-called barriers.These can be obtained either by changing the refractive index pro?le or the?lling factor of the two con-stituting crystals or even also by approaching two PhC layers of different lattice period.Although the concept of photonic crystal heterostructures has already been employed in several applications,however,the inclusion of heterostructures in both photonic crystal re?ectors of PCM-VCSELs represents to our knowledge an original and innovative solution for a quasi-3D light con?nement in such devices.

Here follows the manuscript organization.In Section2,a brief description of the structure design and the photon kinetics describing the vertical con?nement in PCM-VCSELs is pro-vided,while in the?rst part of Section3the crucial concept of light transport kinetics within1-D PCMs is addressed by pre-senting the two-dimensional dispersion surfaces of slow Bloch modes excited in the mirror.In the second subsection the the-oretical description is validated by3-D FDTD simulations and the integration of photonic crystal heterostructures in PCMs is introduced and discussed.In the third and last part of Section3 the experimental evidence of previous theoretical arguments is

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Fig.2.(a)RCWA-computed TE-and TM-re?ectivity spectra(inset)of1-D PCMs.(b)Dispersion characteristics in the neighbourhood of the-point of slow Bloch modes excited via the low-Q Fano resonances(labelled as“FR”) shown in the TE-re?ectivity spectrum.

presented;?nally,Section4is dedicated to conclusions and per-spectives.

II.PCM-VCSEL S TRUCTURE AND V ERTICAL C ONFINEMENT A schematic cross section of the optically pumped structures under study along with its top view is given in Fig.1.Brie?y, an embedded InAsP-InGaAsP multiple-quantum-well active re-gion grown by molecular beam epitaxy(MBE),such to pro-vide gain around1.55m,is placed between a top and bottom Si/SiO1-D PCMs broadband re?ectors(50%Si?lling factor, lattice period m)spaced by means of two sym-metric SiO gaps.It is worth to point out that the use of ad-vanced III-V—semiconductors/SiO wafer bonding technology [41],[42]as well as deep-UV(DUV)lithography is required for mirrors fabrication.

The light kinetics that governs the vertical con?nement in PCM-VCSELs can be described in rather good approximation by simply evaluating the quality factor of the exploited Fano resonance.According to the relation(strictly rig-orous only in the case of laterally in?nite photonic crystal mem-branes),where and are,respectively,the frequency and the lifetime of photons in the membrane,a broad resonance cor-responds to a strong coupling rate of photons to the ra-diation continuum,which represents a condition to obtain wideband mirrors.

A rigorous coupled-wave analysis(RCWA)computation of PCM re?ectivity spectra for transverse electric(TE,electric ?eld parallel to silicon slits)and transverse magnetic polar-ization(TM,electric?eld perpendicular to slits)is shown in Fig.2(a),while the dispersion characteristics of slow Bloch modes corresponding to both Fano resonances are reported in Fig.2(b).The calculation of dispersion curves was carried out by tracking the resonant wavelength of the corresponding Fano resonance.This method,which may appear a qualitative approximation due to the small quality factors involved,proves instead to be enough reliable in determining the frequencies of slow Bloch modes located at band-edges,resulting in a very good agreement with3-D FDTD simulations of the PCM-VCSEL cavity shown later on in this work.

Designed in order to operate at a band-edge obviously situ-ated above the light cone,the PCM shows a wide TE stopband (140nm)provided by two spectrally overlapped broad reso-nances situated at1.37m and1.55m respectively.It should be remarked that both slow Bloch modes can couple at the -point,given their symmetric distributions over the photonic crystal unit cell[43].Although a high power re?ectivity is ensured over the whole PhC stopband,however we decided to operate near the redder Fano in order to maximize the cavity vertical con?nement in the wavelength region of interest.The guidelines for a proper choice of the Fano resonance lie in its dispersion characteristic and we will comment further on it below.

As said before,the optical mode supported by the cavity can be seen as a hybrid mode made up of two components:a wave-guided component in the mirrors as well as a radiated(com-monly called Fabry-Perot)component in between the mirrors. In detail,one can express the average relative time spent by pho-tons in the cavity during the overall lifetime of the hybrid reso-nance as follows[24]:

(1)

where,being the cavity optical thickness and c the speed of light.In contrast with low-index contrast DBRs, the fast coupling rate to radiation continuum provided by broad Fano resonances promotes a higher electromagnetic density within the laser active region,thus favouring the design of low-threshold devices.

III.A DDRESSING THE L ATERAL C ONFINEMENT IN

PCM-VCSEL S

A.Light Transport Kinetics in1-D Photonic Crystal Mirrors Given the?nite width of the photonic crystal membrane re-?ector,the re?ectivity yield is limited by the lateral escape rate which is in turn related to the average group velocity ex-by photons when propagating in PCMs.Therefore, concerning the issue of lateral con?nement,a second necessary condition to realize ef?cient mirrors is set by minimization of ,where and indicate,respectively,the lat-eral of the mirror and the Fano resonance dispersion char-acteristic curvature around the-point[23].

In other words,the resonant coupling ef?ciency can be ex-pressed as:the reduction in lateral losses is thus accomplished by putting photons through a slow-light regime via the excitation of surface-addressable slow Bloch modes located at very?at band-edges(low)of dispersion curves.

The dispersion characteristic of the hybrid mode is entirely de?ned by its wave-guided and radiated components in the re-ciprocal space.The isotropic dispersion characteristic of the FP component of the hybrid mode in the vicinity of the-point can be described by the following simple analytical expression

(2) where indicates the transverse wavevector component,being the frequency at the-point and the quadratic approx-imation of the dispersion characteristic curvature evaluated at the band-edge.In a simpli?ed but still reliable one-dimensional approach(strictly rigorous in case of laterally in?nite struc-tures),the hybrid mode band curvature is a linear combi-nation of the wave-guided and FP components

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corresponding band curvatures weighted by the relative average lifetimes and[28]

(3) Owing to the isotropic dispersion characteristic of the Fabry–Perot component of the hybrid mode,it follows that the optical cavity modal features are mainly determined by the wave-guided component.Consequently,a deep study of photons behavior when exciting slow Bloch modes in PCMs is essential to the understanding of the physics describing the device.Given the one-dimensional nature of the membrane refractive index structuring,photons propagating in PCMs experience different dispersion curves depending on the wave vector,thus originating strongly anisotropic two-dimensional dispersion surfaces.

Relying on purely one-dimensional dispersion characteristics as commonly done would end up with the unrealistic modelling of light transport in the mirrors.We need to shift to dispersion surfaces where the energies of corresponding photonic states are now depending on a generic in-plane wave vector of compo-nents.

In this way,grasping the?ow of light within photonic crystal membrane re?ectors provides us with a powerful tool to design highly compact and innovative single-mode PCM-VCSELs. Such complex picture has been studied by RCWA calcula-tions in the neighbourhood of the-point,which,in our case, corresponds to the domain of the reciprocal space experienced by the wave-guided component of the fundamental mode.As il-lustrated in Fig.3the-space dispersion surfaces show,beyond the well-expected anisotropy,very different behaviors.The slow Bloch mode at1.55m is described by a saddle surface, while the mode at higher energy is characterized by a strongly anisotropic paraboloid.Although both resonances provide high vertical con?nement[see Fig.2(a)],the latter is affected by stronger lateral losses due to a higher average group velocity notably along the direction perpendicular to the mirror slits and should therefore be considered less appropriate for an ef?cient con?nement of optical modes.On the other hand,it can be noted that both dispersion surfaces are sharing a?at but slightly negative curvature mainly parallelly to the slits.The existence of directions within PCMs along which photons propagate with a negative group velocity allows con?ning the light towards the mirror center,resulting crucial for the improvement of light control in the device as further shown later on.

According to(3),we may suppose to exploit slow Bloch modes characterized by a negative curvature of the dispersion characteristic at the band-edge in order to com-pensate for the positive band curvature of the Fabry–Perot mode(2),resulting in a minimization of the global hybrid mode curvature over a wide reciprocal space domain around the-point.The enhanced light slow-down would turn out in high-Q cavity modes.Nevertheless,the strong anisotropy of 2-D dispersion surfaces prevents to accomplish an overall com-pensation between and for every in-plane direction. In other words,(3)should be re-written as a function of the in-plane wave vector and not just of.As a re-sult,innovative con?nement strategies are

necessary.

To this purpose,2-D dispersion surfaces represent a highly predictive and reliable tool for the design of2.5-D laser cavities.Fig.3.Two-dimensional reciprocal-space dispersion surfaces of slow Bloch modes at1.37m(a)and1.55m(b)respectively.

In fact,although the hybrid mode spans in a three-dimensional world,however,its wave-guided(and most meaningful)com-ponent can be considered as purely two-dimensional.Hence,the picture describing the light behavior in the mirrors is thus given by dispersion surfaces which depend exclusively on in-plane wave vectors.

On the basis of the morphology of dispersion surfaces[see Fig.3(b)]as well as referring to the considerations contained in the previous paragraph,we can infer that photons travel-ling within PCMs will experience a lateral con?nement or,vice versa,a higher lateral escape rate,depending on the wave vector. Speci?cally,photons propagating in the mirrors along directions characterized by a negative group velocity are to a certain ex-tent con?ned within the mirror.

Simply,starting from the de?nition of group velocity for the th dispersion band

(4) we can determine con?nement and decon?nement domains in the reciprocal space by computing the gradient of the Fano res-onance dispersion surface at1.55m(mode“B”)as illustrated in Fig.4.By deriving the group velocity as a two-dimensional vectorial?eld we obtain a clearer overview about the magnitude and preferential directions along which lateral losses rise sig-ni?cantly.We expect the out-coupling of light to be maximized along those directions(i.e.,wave vectors)indicated by the gra-dient.Thus,mirrors reveal to be particularly leaky across the slits,while showing a natural con?nement along the slits.Con-cerning single-mode operation,gradient paths in Fig.4clearly explain the achievement of transverse modal selection in the de-vice:those modes characterized by larger transverse wavevector components are leaking out of the PCM faster,resulting in an in-trinsic modal discrimination determined by the curvature of dis-persion surfaces.The increased lateral losses suffered by higher

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Fig.4.(a)–(d)Group velocity corresponding to the slow Bloch mode at1.55 m[see.Fig.3(b)]calculated on different-space domains.

order modes boost the threshold discrimination for the bene?t of the fundamental mode.

B.Heterostructure-Con?ned1-D PCMs for Ultimate Transverse Light Control

Given the high vertical con?nement obtained when operating nearby the Fano resonance wavelength,the minimization of photons lateral escape rate within the PCMs is necessary for low-loss PCM-VCSELs.

The introduction of a photonic crystal heterostructure suits quite well with the control of anisotropic losses arising from the peculiar light transport dynamics taking place in1-D PCMs.In our devices,barriers are obtained by introducing a local vari-ation of the?lling factor(silicon content)and oriented per-pendicularly to those directions affected by a higher average group velocity,aiming at preventing photons to leak out and al-lowing a more ef?cient optical transverse con?nement[35][see Fig.5(a)].

Similarly to the formalism used in[38]

we can express the local modi?cation of the?lling factor in the heterostructures Fig.5.(a)Sketch-up of a heterostructure-con?ned1-D photonic crystal mirror. Barriers are introduced in a typical1-D PCM to enhance lateral con?nement (and represent,respectively,the silicon?lling factor in the well and barriers).(b)Schematic illustration of the heterostructure band-gap;the tun-nelling and diffraction losses coupling rates are indicated.(c) dispersion characteristics in the well and barriers .indicates the con?nement frequency along direction of transport.

as a spatially slowly varying perturbation modulating the average refractive index of the crystal

(5) where2L and are,respectively,the width of the well and the index contrast between the core and the cladding of the het-erostructure.

In a na?ve but realistic approach,the heterostructure can be seen as a resonator where barriers serve as mirrors,while the well constitutes the centre cavity.The resulting con?nement wavelength range arises from the bandgap introduced with the heterostructure and can be treated as an energy barrier[

in Fig.5(c)].The lateral re?ectivity provided by the heterostruc-ture bandgap increases the lifetime of the wave-guided mode in the PCM,promoting the con?nement of the global hybrid mode.In particular,in narrow barriers with a tiny heterostruc-ture bandgap the electric?eld decays exponentially but still al-lowing photons to pass through as in quantum-mechanical tun-nelling.On the contrary,in the case of wider and energetic bar-riers,the decay will be complete so that all the energy will be re?ected within the well.This mechanism is responsible for the enhancement of the photonic crystal mirror re?ectivity yield. In dielectric waveguides optical con?nement is obtained when the dielectric contrast between core and cladding is posi-tive.In photonic crystal heterostructures,the diffractive-based con?nement of waveguided modes depends on the sign of the th band curvature in the well at the band-edge[38](i.e., the photon effective mass

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evaluated along the direction of perpendicular transport.The positive band curvature along implies that optical con?ne-ment can be obtained if the average refractive index in the well is greater than in barriers,which implies the use of a higher silicon?lling in the On the contrary,using

in presence of a positively-(negatively-) curved dispersion band in the well would introduce antiguiding at the expense of modal con?nement in the VCSEL. Regarding modal selection between two competing trans-verse modes,the single-mode behavior of a laser microcavity is usually assessed through the modal stability parameter

(6) where the subscripts and label,respectively,vertical and hor-izontal mode orders and represents the threshold gain the corresponding mode needs for lasing.Alternatively,modal se-lection can be appreciated to a larger extent by estimating the proportion between the quality factor of competing modes,since it provides the ratio between the energy stored in the cavity and the dissipated power for each cavity mode.In order to lay out an accurate comparison between heterostructure-con?ned devices and ordinary PCM-VCSELs in terms of their modal properties, rigorous3-D FDTD simulations(without considering the gain medium)were performed.

In Table II resonant wavelengths and corresponding quality factors of the fundamental and?rst order transverse modes are reported for a standard15-m-wide PCM-VCSEL with and without the use of lateral barriers. Results con?rm the expected increase in lateral con?nement of cavity modes provided by heterostructure-con?ned photonic crystal mirrors respect to standard1-D PCMs.This can be fully appreciated by comparing the cavity modes near?elds reported in Fig.6(a)–(d).First of all,lateral losses are strongly anisotropic and this perfectly matches with the description provided by dispersion surfaces:photons loss rate across the mirror slits is sensibly higher respect to the parallel direction [see Fig.6(a),(b)].Moreover,the same behavior is reproduced in the MQW active region,implying that the modal properties of the hybrid mode are shaped by its wave-guided component in the mirror.In second place,the heterostructure-con?ned mirrors[see Fig.6(c),(d)]suppress lateral loss almost com-pletely,resulting in a considerable quality factor enhancement originated by the maximization of the PCMs re?ectivity yield. The observed red-shift of cavity modes in structures including photonic heterostructures is simply due to the variation of the transverse boundary.

Referring to Table II,we observe that the rise in the funda-mental mode quality factor does not come at the expense of the modal selection,but,on the contrary,strengthens the modal dis-crimination of the cavity.The reason for that can be found out by introducing in our descriptive model two additional parame-ters[see Fig.5(b)]:

1)the photons tunnelling rate through the barriers,

which expresses the ef?cacy of the heterostructure in con-?ning the light laterally;

2)a second

term related to diffraction loss affecting cavity modes,which is induced by the perturbation modu-lating the refractive index pro?le.Fig.6.near?elds within the top PCM(a)and the MQW active region

(b)in standard PCM-VCSELs compared to a heterostructure-con?ned device

(c),(d).Mirror dimensions are de?ned by the superimposed white square(co-ordinates are reported in

m),while slits orientation is illustrated schematically in the left part of the

TABLE II

M ODAL B EHAVIOR C OMPARISON Consequently,we can de?ne the quality factors of transverse

modes as follows:

(7) where refers to out-coupling vertical losses which mainly depend on modal wavelengths.

The increase in lateral re?ectivity yield provided by het-erostructure is strictly linked to the width of the bandgap originated by the perturbation.In particular,the exponential decay of the electric?eld characterized by penetration depth within barriers is related to the size of the heterostructure band-gap.Residual lateral losses are thus mainly con-trolled by the barriers physical extension as well as the width of the con?nement frequency range.

Modal selection is related to diffraction losses stem-ming from the different spatial overlap of transverse modes with barriers.In detail,the coupling to radiation continuum via diffractive scattering due to barriers is proportional to the overlap between the optical mode and the perturbation to the dielectric constant introduced in the photonic crystal mem-brane.The mode overlap with barriers affects also the photons tunnelling rate.In fact,a major extension of the cavity mode pro?le within barriers gives rise to a drop in re?ectivity yield due to a diminished ef?cacy in the con?nement.It follows that barriers position governs the selective lateral con?nement

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introducing threshold discrimination owing to the increased diffraction and lateral loss experienced by higher order modes respect to the lowest order lasing mode.

The heterostructure bang-gap is assessed as a function of [see Fig.7(a)]by means of RCWA calculations.Given the pe-culiarity of the behavior,a focused digression is required.We can in fact distinguish four different operation regimes:

1)a strong antiguiding region for;

2)a guiding region for weak perturbations where the gap

width increases almost linearly with;

3)for a growing perturbation,a weakly-guiding region takes

place originated by the onset of the bandgap shrinkage.

For a certain critical value of the perturbation the bandgap reaches its vanishing-point where the diffractive optical con?nement turns off owing to the free propagation of photons in the barriers;

4)for barriers and well swap roles and the het-

erostructure becomes again antiguiding for the optical mode.

Hence,the diffractive con?nement of wave-guided modes in the well vanishes for a critical perturbation,and,for ,the heterostructure displays even an antiguiding effect on the optical mode.This should not surprise given that in[38] authors assumed a modest perturbation causing weak coupling between bands.Depending on the magnitude of the perturbation introduced in the dielectric constant pro?le of the heterostruc-ture,the corresponding modi?cation of the band structures in the barriers along the direction of perpendicular transport deter-mine guiding or even antiguiding of the optical mode.

To account for the impact of heterostructures on PCM-VCSEL modal properties as well as to validate the reliability of the approximation done when computing the heterostructure bandgap by RCWA,transverse modes quality factors are shown as a function of in Fig.7(b).The evolution of heterostruc-ture bandgap[see Fig.7(a)]is in very good agreement with the transverse modes quality factors and near?eld pro?les calcu-lated by3-D FDTD.The existence of guiding,weakly-guiding and antiguiding regimes is fully con?rmed.In particular,while a small modulation of the dielectric constant is needed for an effective light trapping within the well,for growing perturba-tions the combined effects of bandgap shrinkage and onset of diffraction both contribute to the drop in quality factor. Beyond the bandgap vanishing-point,transverse modes suffer a sudden drop in lateral con?nement due to the het-erostructure-induced antiguiding.This is explained by the role reversal between barriers and well which takes places when or.Photons can propagate to the sides of the heterostructure owing to the bandgap inversion between lateral wells(former barriers)and the central barrier(former well).This induces antiguiding on the optical mode,impinging on the lateral con?nement of the wave-guided component and, in turn,causing the quality factor to fall consistently.Besides, the slight discrepancy between the different values of deter-mined by RCWA(black dashed line)and FDTD(grey dotted line)respectively is ascribable to the onset of diffraction losses smearing out the

abrupt con?nement switch-off(for) caused by the vanishing heterostructure band-gap.Fig.7.(a)RCWA-computed heterostructure bandgap as a function of the per-turbation:beyond the bandgap vanishing-point the heterostructure becomes antiguiding for the optical mode.(b)the heterostructure perturbation on the cavity modal features:transverse modes quality factors to-gether with corresponding FDTD-computed near?elds for the mode at the MQW section(insets)are illustrated.

C.Micro-Photoluminescence Measurements

With the purpose of con?rming the reliability of the theoret-ically-predicted photons transport in one-dimensional PCMs as well as the possibility to selectively introduce guiding or antiguiding in the devices by means of heterostructure-con-?ned mirrors,infrared(IR)micro-photoluminescence(-PL) observations have been performed on the?rst-ever fabricated devices for optical pumping.Scanning electron microscope (SEM)cross section images of devices are reported in Fig.8. The PCM-VCSEL was optically pumped at room temperature using a pulsed laser diode emitting at808nm.The pulsewidth is70ns,with a repetition rate of2.3MHz,while a10-m-wide pump spot[see Fig.9(a)]is obtained on the sample by means of a Mitutoyo50X near-infrared(NIR)objective lens with numerical aperture(NA)equal to0.42.The signal emitted from the sample was collected back through the same objective lens and re?ected into a Xenics IR camera via a beam splitter.The distribution of-PL emission reported in Fig.9(a)–(c)com-pares very well with the theoretical considerations concerning anisotropic light transport in these mirrors.While-PL spot is subjected to a slight but appreciable compression along the direction parallel to the mirror slits[see Fig.9(b)],on the other hand,light experiences considerable losses when propagating along the perpendicular direction[see Fig.9(c)],con?rming the nature of slow Bloch modes dispersion surfaces in1-D PCMs shown in the?rst part of this section.With the sole purpose of providing the reader with a clearer visualization of

2022JOURNAL OF LIGHTWA VE TECHNOLOGY,VOL.29,NO.13,JULY1,

2011

Fig.8.(a)–(d)SEM images of fabricated PCM-VCSELs for optical pumping. In detail,the topology transfer of the Si top mirror after SiO-regrowth(a)and the bottom mirror(b)are reported.Close-up shots on the bonding interface(c) and the III-V part of the laser microsource(d)are shown as well.

the anisotropic losses,the PL spot has been moved to the left bottom corner of the PCM;however,the photoluminescence emission undergoes the same deformation,whatever the posi-tion assumed in the mirror.

Afterwards,the experiment was carried out on PCM-VC-SELs employing a photonic crystal heterostructure in both mir-rors.In order to prove the actual capability of?nely tailoring purposely introduced guiding and antiguiding in these struc-tures,two devices characterized by a different heterostructure bandgap(owing to an opposite sign in the perturbation to the refractive index pro?le)have been tested.Also in this case, experimental results illustrated in Fig.9(d)–(f)show very good agreement with theoretical arguments and ab initio simulations presented in the previous section.In particular,when pumping guided devices[see Fig.9(e)],the spot of-PL emission ex-hibits no losses in the direction of perpendicular transport thanks to the ef?cient minimization of lateral escape rate provided by barriers,while still presenting a slight con?nement in the direc-tion of parallel transport.

On the contrary,the bandgap inversion characteristic of an-tiguiding heterostructures implies free propagation of photons to side wells as clearly shown in Fig.9(f).Furthermore,the split-ting of the-PL emission spatial pro?le in three distinct areas highlights the presence of a bandgap in the darker region taking place between the central spot and the remaining photolumines-cence in lateral wells.

IV.C ONCLUSION

The use of heterostructures in PCMs paves the way for a new generation of single-mode VCSELs where lateral con?nement and higher order modes suppression are accomplished jointly without either

turning to index-or gain-guiding mechanisms and/or resorting to selective mode lensing[8].Differently Fig.9.Infrared camera shots of-PL emission out of VCSEL’s top PCM at RT.In each panel a schematic illustration in the bottom left corner provides the actual orientation of the PCM during the experiment.A strong anisotropic light transport characterizes1-D photonic crystal mirrors(a)–(c):photoluminescence emission is evidently compressed along slits(b)while experiences losses in the perpendicular direction(c).(d)–(f)A photonic crystal heterostructure is intro-duced to enhance and tailor the light control in PCMs.(e)Guiding

and(f)antiguiding barriers are shown in real devices.

from classic VCSEL structures,the engineering of heterostruc-ture-con?ned one-dimensional photonic crystal mirrors allows a broad tailoring of the cavity modal features(single-mode operation and polarization control)along with the implemen-tation of ef?cient guiding as well as antiguiding which are purely based on diffractive phenomena.Furthermore,the use of high-Q optical modes will allow lasing operation at a lower threshold in optically and electrically pumped VCSELs:this would also reduce dramatically the drawbacks related to the device heating.It is authors’intention to deepen the aspects linked to the lasing behavior of such devices in a future dedi-cated communication.

Summarizing,on the basis of both theoretical and experi-mental approaches,we studied the nature of optical con?nement in PCM-VCSELs by assessing the two-dimensional-space properties of slow Bloch modes in1-D photonic crystal membrane re?ectors.An exhaustive comprehension of light transport phenomena in PCMs was essential for achieving an ultimate light con?nement as well as promoting improved cavity modal behavior.To this purpose we showed that the introduction of photonic heterostructures in such mirrors represents a viable and robust design innovation for the real-ization of compact high-Q single-mode polarization-controlled 2.5-D laser cavities.Finally,the diffractive-based con?nement scheme ruling light transport kinetics and modal properties in

SCIANCALEPORE et al.:QUASI-3D LIGHT CONFINEMENT2023

PCM-VCSELs reveals to be indisputably more ef?cient and ?exible respect to prior refractive approaches.

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Corrado Sciancalepore was born in Molfetta,Italy.He received the M.S.de-gree in physical engineering in2009from Politecnico di Torino,Italy.Under the European project SUBTUNE,he received the M.Sc.degree on the design and optimization of GaAs-and InP-based widely tunable VCSELs.

In December2009he joined the Nanophotonics team at the Institut des Nanotechnologies de Lyon(INL)/Centre National de la Recherche Scienti?que (CNRS),Lyon,France,to write a doctoral dissertation regarding innovative proof of concepts for the integration of photonics on Silicon.His work is fruit of the close collaboration in the framework of the EC-funded project HELIOS between the French CNRS and the Optronics Department of Commissariat àl’Energie Atomique-Laboratoire d’Electronique et de Technologies de l’Information(CEA-LETI)of Grenoble,France.

Badhise Ben Bakir received the M.S.degree in physics from UniversitéClaude Bernard,Lyon,France,in2003,and the Ph.D.degree in optical and electrical engineering from Ecole Centrale de Lyon,Ecully,France,in2007.

Later that same year,he joined the Optronics Department of Commissariatàl’Energie Atomique—Laboratoire d’Electronique et de Technologies de l’Infor-mation(CEA-LETI),Grenoble,France.His research interests include physics of optoelectronic devices and nanostructures as well as micro-nano-fabrication related to Si and III-V based materials for optical integrated circuits.

Xavier Letartre received the Ing.Dipl.degree in1987from the Institut Su-perieur d’Electronique du Nord,France,and the Ph.D.degree in material sci-ences from the Universitédes Sciences de Lille,France,in1992.

He joined INL,Ecole Centrale de Lyon,Ecully,France,in1992.He is cur-rently Research Director at CNRS,Ecole Centrale de Lyon.His areas of interest include physics of optoelectronic devices,photonic crystals,and nanostructures for optical devices and circuits.

Jean-Marc Fedeli received the electronics engineer diploma from INPG Grenoble,France,in1978.

Then he conducted research at the CEA-LETI and acted for two years as advanced program Director in Memscap company for the development of RF-MEMS before he returned to CEA-LETI in2002as coordinator of silicon photonic projects.His main focus is on the integration of a photonic layer at the metallization level of an electronic circuit.He has been participating on different European FP6projects(PICMOS,PHOLOGIC,MNTE,ePIXnet). Under the European FP7,he is involved in the WADIMOS and PhotonFAB (ePIXfab)projects and managing the HELIOS project.Nicolas Olivier received the technologic diploma from Saint-Etienne Univer-sity,Saint-Etienne,France in2000.

In the same year,he joined the Commissariatàl’Energie Atomique(CEA) Valduc.He worked on fabrication of MegaJoule’s laser microtargets.In2005, he joined the Laboratoire d’Electronique et de Technologie de l’Information (CEA-LETI),Grenoble,France.He has been involved in the MOSEL Euro-pean project for the fabrication of single-mode1.3-m-emitting VCSELs.In 2008,he joined the Silicon Photonics Group where he is currently in charge of III-V materials processing.He works on various technological aspects of sil-icon-based photonics.He is presently involved in the HELIOS and WADIMOS European projects.

Damien Bordel received the engineering degree in materials science from the Institut National Polytechnique de Grenoble,Grenoble,France,in2004and the Ph.D.degree in materials and surfaces science from the Ecole Centrale de Lyon (ECL),Ecully,France,in2007.

From June2008to November2009,he was with Tokyo University,Japan, working on MOCVD growth and processing of GaAs quantum dots laser devices.In November2009he joined the Commissariatàl’Energie Atom-ique/Laboratoire d’Electronique de Technologie de l’Information(CEA/LETI), Grenoble,where he is currently in charge of wafer bonding development for photonic applications.

Christian Seassal graduated from Institut National des Sciences Appliquées de Lyon,France,in1993,and received the Ph.D.degree in condensed matter in 1997from Ecole Centrale de Lyon,France.

He joined the INL/CNRS,Ecole Centrale de Lyon as a CNRS Researcher in1998.His research activities have concerned Micro-Opto-Electro-Mechan-ical Systems(MOEMS)based on III-V compound semiconductors.His current research interest concerns photonic crystals and nanostructures for integrated photonics and photovoltaics.

Pedro Rojo-Romeo(M’09)received the Ing.Dipl.degree in physics in1981 from the Institut National des Sciences Appliquées(INSA)in Lyon,France, and the Ph.D.degree in electronic devices in1984at INSA,Lyon,France.

He is currently an Associate Professor(since1988)in electronics at Ecole Centrale de Lyon(France),at the Institute of Nanotechnologies of Lyon(INL). His primary research interests include electrical and optical device fabrication technology,characterization of microelectronic and optoelectronic micronan-odevices.He is also involved in optical interconnection systems,nanotechnolo-gies,and optical integrated circuits technologies.

Philippe Regreny was born in France,in1967.He received the M.Sc.degree in materials sciences from Rennes University,Rennes,France,in1991,and the Ph.D.degree in electronics from Ecole Centrale de Lyon,Lyon,France,in1997. Since1998he has been a Research Engineer at Institut des Nanotechnologies de Lyon(INL)/Centre National de la Recherche Scienti?que(CNRS),Ecole Centrale de Lyon.He has authored or coauthored80publications.His current research interests include epitaxial growth of III-V semiconductors and oxide materials and their integration on silicon.

Pierre Viktorovitch is Research Director at INL/CNRS,Ecole Centrale de Lyon,Ecully,France.

His research activities have been concerned with silicon microelectronic devices,photovoltaic solar-energy-conversion devices based on amorphous silicon,III-V compound semiconductor microelectronic devices.His current research interests concern micro-opto-electro-mechanical systems(MOEMS) based on III-V compound semiconductors,micronanophotonic devices (especially based on photonic crystals)and III-V/silicon/active-passive hetero-geneous or hybrid integration.

SDN及ODL概括性总结

1、SDN是什么？ SDN(Software Defined Network)即软件定义网络，是一种网络设计理念。网络硬件可以集中式软件管理，可编程化，控制转发层面分开，则可以认为这个网络是一个SDN网络。SDN 不是一种具体的技术，不是一个具体的协议，而是一个思想，一个框架，只要符合控制和转发分离的思路就可以认为是SDN. 2、传统网络面临的问题？ 1）传统网络部署和管理非常麻烦，网络厂商杂，设备类型多，设备数量多，命令行不一致2）流量全局可视化难 3）分布式架构中，当网络发生震荡时，网络收敛过程中，有可能出现冗余的路径通告信息4）网络流量的剧增，导致底层网络的体积膨胀、压力增大；网络体积越大的话，需要收敛的时间就越长 5）想自定义设备的转发策略，而不是网络设备里面的固定好的转发策略 -------->sdn网络可以解决的问题 3、SDN的框架是什么 SDN框架主要由，应用层，控制层，转发层组成。其中应用层提供应用和服务（网管、安全、流控等服务），控制层提供统一的控制和管理（协议计算、策略下发、链路信息收集），转发层提供硬件设备（交换机、路由器、防火墙等）进行数据转发、 4、控制器 1）控制器概述 在整个SDN实现中，控制器在整个技术框架中最核心的地方控制层，作用是上接应用，下接设备。在SDN的商业战争中，谁掌握了控制器，或者制定了控制器的标准，谁在产业链条中就最有发言权 2）控制器功能 南向功能支撑：通过openflow等南向接口技术，对网络设备进行管控，拓扑发现，表项下

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但这种分离是封闭在被称为“盒子”的交换机或路由器上，不可编程；另一方面，从IP网络的维度来考虑，采用的是分布式控制的方式：在控制面，每台路由器彼此学习路由信息，建立各自的路由转发表；在数据面，每台路由器收到一个IP 包后，根据自己的路由转发表做IP转发； IP网络的这种工作方式带来了运维成本高、业务上线慢等问题，并越来越难以满足新业务的需求，传统上通过添加新协议、新设备等手段来缓解问题的方式，收益越来越少。穷则思变，许多人产生了革命的想法，现有的网络架构既然无法继续演进发展，为何不推倒重来，重新定义网络呢？真可谓“时势造英雄”，2006年斯坦福大学Nick McKeown教授为首的研究团队提出了OpenFlow的概念用于校园网络的试验创新，后续基于OpenFlow给网络带来可编程的特性，SDN （Software Defined Network）的概念应运而生。 SDN将原来封闭在“盒子”的控制平面抽取出来形成一个网络部件，称之为SDN 控制器，这个控制器完全由软件来实现，控制网络中的所有设备，如同网络的大脑，而原来的“盒子”只需要听从SDN控制器的命令进行转发就可以了。在SDN 的理念下，所有我们常见的路由器、交换机等设备都变成了统一的转发器，而所有的转发器都直接接受SDN控制器的指挥，控制器和转发设备间的接口就是OpenFlow协议。其简单模型如图所示：

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Distort扭曲特效 --Bezier warp贝赛尔曲线弯曲 --Bulge凹凸镜 --CC Bend It 区域卷曲效果 --CC Bender 层卷曲效果 --CC Blobbylize 融化效果 --CC Flo Motion 两点收缩变形 --CC Griddler 网格状变形 --CC Lens 鱼眼镜头效果，不如Pan Lens Flare Pro --CC Page Turn 卷页效果 --CC Power Pin 带有透视效果的四角扯动工具，类似Distort/CornerPin --CC Ripple Pulse 扩散波纹变形，必需打关键帧才有效果 --CC Slant 倾斜变形 --CC Smear 涂抹变形 --CC Split 简单的胀裂效果 --CC Split 2 不对称的胀裂效果 --CC Tiler 简便的电视墙效果 --Corner pin边角定位 --Displacement map置换这招 --Liquify像素溶解变换 --Magnify像素无损放大 --Mesh warp液态变形 --Mirror镜像 --Offset位移 --Optics compensation镜头变形 --Polar coordinates极坐标转换 --Puppet木偶工具 --Reshape形容 --Ripple波纹 --Smear涂抹 --Spherize球面化 --Transform变换 --Turbulent displace变形置换 --Twirl扭转 --Warp歪曲边框

--Wave warp波浪变形 Expression Controls表达式控制特效 --Angel control角度控制 --Aheckbox control检验盒控制 --Color control色彩控制 --Layer control层控制 --Point control点控制 --Slider control游标控制 Generate 渲染 --4-ccolor gradient四角渐变 --Advanced lightning高级闪电 --Audio spectrum声谱 --Audio waveform声波 --Beam光束 --CC Glue Gun 喷胶效果 --CC Light Burst 2.5 光线缩放 --CC Light Rays 光芒放射，加有变形效果--CC Light Sweep 过光效果 --Cell pattern单元图案 --Checkerboard棋盘格式 --Circle圆环 --Ellipse椭圆 --Eyedropper fill滴管填充 --Fill 填充 --Fractal万花筒 --Grid网格 --Lens flare镜头光晕 --Paint bucker颜料桶 --Radio waves电波 --Ramp渐变 --Scribble涂抹 --Stroke描边 --Vegas勾画 --Write-on手写效果

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********项目尽职调查及投资分析报告 ****基金 二零一二年十一月

摘要 ●公司简介 公司名称： 所属行业： 注册资本： 注册地址： ●项目简介 ●本次融资方案： ●盈利预期 ●上市计划 。

目录 第一部分本次投资概要 (6) 1.1 目标公司概况 (6) 1.2 融资主体 (6) 1.3投资方案 (6) 1.4 投资亮点 (6) 1.4.1 国家大力支持行业 (6) 1.4.2 行业发展前景广阔 (6) 1.4.3 技术优势 (6) 1.4.3 人力 (7) 1.5 投资风险管理 (7) 1.5.1 产品进入市场风险 (7) 1.5.2 生产风险 (7) 1.5.3 财务风险 (7) 1.5.4 团队管理风险 (7) 第二部分公司基本概况 (7) 2.1 公司简介 (7) 2.2 历史沿革及股权变更 (7) 2.3 公司组织机构 (8) 2.3 公司管理层 (8) 2.3.1管理层主要人员 (8) 2.3.2管理/技术人员变动情况 (8) 2.3.3管理层团队评价 (8) 2.4 员工结构 (8) 2.5 薪酬结构 (8) 2.5.1薪金制度 (8) 2.5.2奖励计划 (8) 2.5.3保险、福利计划 (8) 第三部分技术及产品 (8) 3.1 主要核心技术 (8) 3.1.1技术来源及所有权情况 (8) 3.1.2 技术先进性 (9) 3.1.3专利情况 (9) 3.1.4 研发能力说明 (9) 3.2 主要产品及特点 (9) 3.2.******************** (9) 3.2.2 国内其他产品比较 (9) 3.2.3 市场壁垒 (9)

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OpenDaylight与Mininet应用实战之复杂网络验证（五） 1多交换机的测试 Mininet中本身就支持多交换机网络拓扑的模拟创建，可通过Python API自定义拓扑创建满足使用者在仿真过程中的多方位需求。 下面举出具体示例验证多交换机支持： 执行此条命令后，查看ODL的Web界面显示的网络拓扑。界面拓扑显示如下： 对所有的虚拟host之间进行互ping操作，通过pingall命令，验证主机间的连通性，继而可验证支持多交换机的功能。

由pingall显示的结果可看出，主机间能够互相通信，且将数据包的流转发给交换机，并由交换机上报给ODL控制器来下发流表使主机通信。 主机通信过程中可查看交换机的流表信息及本身信息。 由交换机流表信息显示可知，控制器通过策略将流表下发到交换机中，使主机发出的数据包转发到下一目的地址。每个交换机查看信息的端口都不同，从第一个交换机端口号为6634开始，以后每一个交换机依次在之前交换机端口号的基础上加1，如第二个交换机的端口为6635。其他交换机的流表信息及自身设备信息可根据此说明进行查看。 2多控制器的测试 多控制器验证支持测试包括两种情况： ■OpenFlow网络中多个同一类型的控制器； ■OpenFlow网络中多个不同类型的控制器； 2.1多个同一类型的控制器验证 测试OpenFlow网络中多个同一类型的controller，比如OpenDaylight，多个ODL之间通过

OpenFlow1.0协议标准交互。 通过Mininet验证，在Mininet中模拟创建的OvS交换机不能指定连接多个控制器，且在同一个Mininet中创建的多个交换机不能指定不同的控制器。所以在验证交换机被多个同一类型的控制器管控时，不能通过用Mininet来验证，但是可通过真实交换机来验证。 如，在真实交换机中设置连接此文中的ODL控制器及另一个ODL控制器，命令为： 连接两个相同类型的ODL控制器，其中192.168.5.203为上述实验使用的控制器，192.168.5.111为另外安装使用的ODL控制器。通过执行如下命令查看交换机连接的控制器信息。 is_connected:true表示交换机都成功连接上控制器。交换机连接到这两个控制器后，控制器通过设备拓扑管理也可以发现此交换机，同时控制器管控存在主备关系，但控制器都可对交换机进行管控、下发流表等操作。 通过真实OpenFlow交换机连接多个控制器，可以实施，且已经验证，控制器和控制器之间存在主备关系，多控制器都可以对连接的交换机进行管控。 2.2多个不同类型的控制器验证 在OpenFlow网络中多个不同类型的controller，比如同时存在NOX和ODL，它们之间如果遵循OpenFlow协议标准的话，也是能够协作工作的。多个不同类型的控制器管控交换机与2.1小节是同样的道理。 如，在真实交换机中设置连接此文中的ODL控制器及其他另一个不同类型的控制器，如POX，命令为： 连接两个不同控制器，其中192.168.5.203为上述实验使用的控制器，192.168.5.111为另外安装使用的POX控制器。经试验验证，ODL与POX都遵循OF1.0版本的协议标准，所以在复杂网络多控制器情况下，只要控制器遵循相同的标准规范，控制器之间可进行对网络的通信管理等。此处实验结果与2.1节一致。交换机连接这两个控制器后，控制器管控存在主备关系，但控制器都可对交换机进行管控、下发流表等操作。 3总结 本文主要对复杂网络多交换机及多控制器的支持验证。因Mininet现在无法模拟多控制器管控一个交换机的情况，所以本专题还是侧重对多交换机的管控实验。至此，OpenDaylight 与Mininet应用实战专题将结束，有介绍不到位或者有疑问的地方请多多指教，互相交流。谢谢！

菜鸟水平初步设置OpenDaylight-OVSDB-+-Openstack测试环境

菜鸟水平初步设置OpenDaylight OVSDB + Openstack测试环境 Hannibal （SDNAP首发） 刚接触SDN和OpenDaylight两个多月时间，还处于人云亦云照葫芦画瓢的水平，在很多大牛的指导文章帮助下，初步搭建一个很简单的OpenDaylight OVSDB + Openstack调试环境。第一次写技术文章，请多包涵。 一、准备 硬件： 双核Core i7，内存4GB，一个以太网卡的Thinkpad X201t，普通个人用笔记本 Host环境： 64位Ubuntu 13.10，OVS 2.0.90 VM环境： 2个Virtualbox VM，Fedora 19 + OVS 2.0.0 + Devstack 。导入Virtualbox都是缺省配置。两个VM的下载地址： https://https://www.wendangku.net/doc/0518043460.html,:443/v1/96991703573236/imgs/Fedora19--2node-Devstack.tar.bz2 Size: 4983728003 bytes MD5sum: dfd791a989603a88a0fa37950696608c 二、原理 OpenDaylight（ODL）是一个由Linux基金会支持，多个网络厂商参与的开源SDN控制器项目。Openstack是开源的IaaS项目。如何让两个平台整合以便更好的发挥作用是本环境搭建的目的。 现有的解决方案之一，就是利用Openstack Neutron的ML2 Plugin，将网络复杂性丢到ODL。也就是说，Openstack通过ML2 Plugin，与OpenDaylight的NB API进行会话，具体网络部署的实现交由OpenDaylight Controller来实现。

Openstack的Ocata版本与opendaylight 的Carbon版本集成详解

Openstack的Ocata版本与opendaylight 的Carbon版本集成详解 作者：胡章丰，zfhu2001@https://www.wendangku.net/doc/0518043460.html, 前提条件 ===================================================================== 1.已搭建好的可用openstack ocata环境一套 2.已下载的opendaylight carbon-sr1发布版本 3.本文档所述环境地址：控制节点：192.168.137.101，网络节点192.168.137.101，计算节点：192.168.137.101,192.168.137.102，ODL控制器节点：192.168.137.100 4.建议ODL控制器节点与Openstack控制节点采用独立节点安装，否则会有端口冲突，需要修改若干配置文件来避免冲突 ===================================================================== 部署opendaylight控制器 ===================================================================== ODL控制器节点执行： 解压缩软件包 tar xzvf distribution-karaf-0.6.1-Carbon.tar.gz cd distribution-karaf-0.6.1-Carbon/ 开启iptables规则（建议将下列规则写入脚本文件，配置开机自动执行，否则每次重启后需要手动添加这些规则） iptables -I INPUT -p tcp --dport 8181 -j ACCEPT iptables -I INPUT -p tcp --dport 8080 -j ACCEPT iptables -I INPUT -p tcp --dport 6640 -j ACCEPT iptables -I INPUT -p tcp --dport 6653 -j ACCEPT 启动odl控制器 ./bin/karaf 安装odl组件（只能装这几个） feature:install odl-netvirt-openstack odl-dlux-core odl-mdsal-apidocs 验证是否安装成功（打开如果是黑板一块，则说明安装成功） 看看能否打开http://ODL控制器节点ip地址:8181/index.html =====================================================================

OpenDaylight的Helium(氦)版本安装

OpenDaylight的Helium版本安装 OpenDaylight（后面缩写ODL）的Helium（氦）版本已发布，具体详情可参考ODL官网。Helium（氦）版本只发布了一个版本，下载链接地址为https://www.wendangku.net/doc/0518043460.html,/software/downloads/helium。官网中分别共享了版本、安装向导、用户向导、开发者向导手册，可进行下载学习。 git clone https://https://www.wendangku.net/doc/0518043460.html,/gerrit/p/integration.git 1.1.Helium安装 此Helium(氦)版本安装研究是基于Ubuntu12.04的基础上进行安装的，此ODL源文件版本是完全可移植的，但是需要Java7.0以上兼容JVM来运行。如果是用到Oracle的话，JDK版本在 1.7.0_45以上。 解压已获取的安装包文件，并进入解压目录： #unzip distribution-karaf-0.2.0-Helium.zip #cd distribution-karaf-0.2.0-Helium/ #cd bin #./karaf##出现问题？ 经验证，此时执行./karaf时，会出现线程异常且No route to host错误，，需要进入上级目录修改文件org.apache.karaf.management.cfg： #cd.. #cd etc #vi org.apache.karaf.management.cfg#打开此文件 将 serviceUrl= service:jmx:rmi://0.0.0.0:${rmiServerPort}/jndi/rmi://0.0.0.0:${rmiRegistryPort}/karaf-${karaf.na me}修改成 serviceUrl= service:jmx:rmi://127.0.0.1:${rmiServerPort}/jndi/rmi://127.0.0.1:${rmiRegistryPort}/karaf-${kar https://www.wendangku.net/doc/0518043460.html,}， 再次进入ODL启动目录： #cd bin #./karaf##执行karaf文件 出现以下正确界面，如图所示：

宏观研究分析框架(上)

试 题 一、单项选择题 1. 根据课程内容，未来在一定程度上是在重复着过去，但并不是在原则上严密地重复着过去，因 此，商业研究预测准确率的边界取决于（ ）。 A. 设计精巧的数理模型 B. 渊博的知识和经验 C. 未来在多大程度上对过去的重复 D. 个人、企业、政府的理性预期 您的答案：C 题目分数：10 此题得分：10.0 2. 根据课程内容，对于一些自然现象、市场变动和经济现象，人们往往会提出各种合乎逻辑的解 释，为了验证解释的正确性，需要将这种解释转化为一个直观、可观察的结果，而这个转化过程 要同时满足三个约束，下列选项中不属于这三个约束的是（ ）。 A. 在逻辑上这种解释一定能够推导出相应的结果 B. 相应的结果只有这种解释能够推导出来 C. 相应结果必须可以很方便、直观地进行观察 D. 这种解释推导相应结果的过程必须建立复杂的数理模型 您的答案：D 题目分数：10 此题得分：10.0 二、多项选择题 3. 根据课程内容，宏观研究分析的基本步骤包括（ ）。 A. 系统性的搜集经验事实，验证理论预测 B. 从理论的内在逻辑出发，提出预测 C. 提出假说，解释现象 D. 观察现象，提出问题 您的答案：A,B,C,D 题目分数：10 此题得分：10.0 三、判断题 4. 无论多么设计精巧的数理模型、多么渊博的知识和经验，商业研究的预测永远做不到百分之百 的确定，其中总会有运气成分发挥作用。（ ） 您的答案：正确 题目分数：10 此题得分：10.0 5. 根据课程内容，与商业的宏观经济研究不同，学校的学术研究更多地是站在中国资本市场参与

者的角度出发分析宏观经济现象，重点思考宏观经济层面数据的变化对资本市场的影响及相互的联系。（ ） 您的答案：错误 题目分数：10 此题得分：10.0 6. 根据课程内容，1996年?2013年中国和美国的年度PPI数据相关性强。（ ） 您的答案：正确 题目分数：10 此题得分：10.0 7. 由于科学技术发展的不可预测性，个人、企业、政府的理性预期和人类认识局限性等原因，未来在原则上并不是过去的简单重复，所以在原则上，未来就是不可预测的。（ ） 您的答案：正确 题目分数：10 此题得分：10.0 8. 金融机构研究人员从事商业研究的目的是做预测，而检验一个金融机构研究成果的最主要标准，甚至可以说是唯一的标准就是预测的准确率。（ ） 您的答案：正确 题目分数：10 此题得分：10.0 9. 根据课程内容，在中国，通货膨胀率的高低直接决定了货币政策松紧，货币政策的松紧又直接决定了金融市场，特别是股票市场流动性的好坏，因此，可以说货币政策的松紧是金融市场运行的最主要外部条件。（ ） 您的答案：正确 题目分数：10 此题得分：10.0 10. 根据课程内容，1981年?1995年中国和美国的年度PPI数据相关性强。（ ） 您的答案：错误 题目分数：10 此题得分：10.0 试卷总得分：100.0