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Silicon is now the most important material in moderm solid state electronics. Regular systems of silicon nanoclusters containing up to 10(exp14)/cm3 elements have been fabricated in a sublattice of opal voids. Structural studies of samples by TEM. HREM and Raman measurements were carried out. The regular lattices of Pt-Si junctions were obtained and their current-voltage characteristics (CVC) were investigated., Pres: 7th Int Symp Nanostructures: Physics and Technology; St Petersburg, Russia. 14-18 Jun 1999. p209-212. This article is from ADA407055 Nanostructures: Physics and Technology. 7th International Symposium. St. Petersburg, Russia, June 14-18, 1999 Proceedings

In conclusion the structural andl optical characterisation of GaN:In epilayers have shown that only a small amount ofin is incorporated into the Ga sites making the layers to be considered as not pure isoelectronically doped. The In atoms presumably occupy interstitial positions in the crystal lattice concentrate on mosaic grain boundaries and have a tendency to form clusters. The In nucleation near structural defects, like e.g. nano-pits. may recover the lattice structure. increasing the integral PL intensity. Besides. like at conventional isoelectronic doping, local strains induced by the inhomogeneous In distribution may activate mechanisms of structure improvement. On the other hand. the possible occupation of interstitials by the In atoms can hardly be considered as a positive factor., Pres: 7th Int Symp Nanostructures: Physics and Technologies, St Petersburg, Russia. 14-18 Jun 1999. p489-490. This article is from ADA407055 Nanostructures: Physics and Technology. 7th International Symposium. St. Petersburg, Russia, June 14-18, 1999 Proceedings

In this paper we study the effect of carrier relaxation processes on Auger recombination in semiconductor quantum wells. It is shown that the calculation in the framework of the conventional perturbation theory is not applicable in the case of narrow wells and wires because of its divergence. Therefore a more rigid Green function techniques is used. The relaxation processes are shown to increase Auger recombination coefficient. however their influence becomes weaker with decrease of the QW width. The transition from the QW to the bulk case is explicitly carried out., Pres: 7th Int Symp Nanostructures: Physics and Technology; St Petersburg, Russia, 14-18 Jun 1999. p386-389. This article is from ADA407055 Nanostructures: Physics and Technology. 7th International Symposium. St. Petersburg, Russia, June 14-18, 1999 Proceedings

Superluminescent diodes (SLDs) operating in 1300-1550 nm wavelength range with high output power (40 mW) wide spectra width (65 nm at FWHM) low modulation depth (< 1%) and singlelobe far field pattern have been fabricated. The optimum SLD is 10% tilted mesa-stripe construction with back absorption section based on broad gain profile InGaAsP/InP separate confinement double heterostructure., Pres: 7th Int Symp Nanostructures: Physics and Technology, St Petersburg, Russia. 14-18 Jun 1999. p150-153. This article is from ADA407055 Nanostructures: Physics and Technology. 7th International Symposium. St. Petersburg, Russia, June 14-18, 1999 Proceedings

Cleaved facets of ZnBeMgSe-based lasers with different design of active region have been studied by means of the cross-sectional atomal (friction) force microscopy (AFM and LFM). A difference in function coefficients has been successfully exploited to image basic layers of the laser diodes. The Be-containing cladding layers and the waveguide area are revealed as regions of lower friction as compared to a GaAs substrate. Elastic strains accumulated at the layer boundaries are displayed via nanometer-high steps and undulations forming in the morphology of the cleaved facets. A remarkable reduction of the elastic strain in the active region containing a (Zn, Cd)Se quantum well has been found for the laser with the specially designed alternately-strained superlattice in the waveguide., Pres: 7th Int Symp Nanostructures: Physics and Technology; St Petersburg, Russia. 14-18 Jun 1999. p220-223. This article is from ADA407055 Nanostructures: Physics and Technology. 7th International Symposium. St. Petersburg, Russia, June 14-18, 1999 Proceedings

We have demonstrated vertical lasing without Bragg reflectors in structure with multiple InGaN/GaN insertions. Laser action is confirmed by superlinear dependence of the output intensity versus excitation density and by appearance of a single lasing mode defined by a vertical Fabry-Perrot cavity formed by GaN/air and GaN/Al2O3 interfaces. Effect of interaction of gain spectrum and cavity modes is demonstrated., Pres: 7th Int Symp Nanostructures: Physics and Technology, St Petersburg, Russia. 14-18 Jun 1999. p124-127. This article is from ADA407055 Nanostructures: Physics and Technology. 7th International Symposium. St. Petersburg, Russia, June 14-18, 1999 Proceedings

Pres: 7th Int Symp Nanostructures: Physics and Technology, St Petersburg, Russia. 14-18 Jun 1999. p380. This article is from ADA407055 Nanostructures: Physics and Technology. 7th International Symposium. St. Petersburg, Russia, June 14-18, 1999 Proceedings

Double heterostructures with spontaneously formed periodical (SFP) InGaAsP/GaAs active regions have been grown. The dependence of photoluminescence (PL) and electoluminescence (EL) properties of SFP InGaAsP/GaAs structures on excitation level and temperature have been investigated. From analysis of linear polarization rate spectral dependencies of PL SFP InGaAsP/GaAs structures it have been determined that domains with different solid phase composition have lattice mismatch (delta alpha) value of opposite sign. Threshold current density 50 A/cm2 at 77 K have been obtained in laser structures. Strong saturation of longwavelength emission hand intensity in room temperature PL and EL spectra with the increase of excitation level have been revealed., Pres: 7th Int Symp Nanostructures: Physics and Technology; St Petersburg, Russia. 14-18 Jun 1999. p154-156. This article is from ADA407055 Nanostructures: Physics and Technology. 7th International Symposium. St. Petersburg, Russia, June 14-18, 1999 Proceedings

The principal mechanisms of Auger recombination (AR) of nonequilibrium carriers in cylindrical quantum wires (QWRs) are investigated. It is shown that there exist two different Auger recombination mechanisms of (i) quasithreshold and (ii) thresholdless types. These mechanisms onginate from the existence of barriers but have different nature. The quasithreshold mechanism is caused by confinement of carriers within the region of a quantum wire which makes the quasi- momentum conservation law approximate and enhances AR process. With increase of the wire radius this process turns to the threshold one. The thresholdless m%echanism relates to the violation of the momentum conservaflon law at the heteroboundary and disappears with the radius tending to infinity., Pres: 7th Int Symp Nanostructures: Physics and Technology, St Petersburg, Russia. 14-18 Jun 1999. p42-45. This article is from ADA407055 Nanostructures: Physics and Technology. 7th International Symposium. St. Petersburg, Russia, June 14-18, 1999 Proceedings

X ray reciprocal space mapping was employed to assess the crystalline quality of the delta-InAs/GaAs superlattices grown at low temperatures and structural transformations related to formation of As-cluster/GaAs superlattices upon post-growth anneal., Pres: 7th Int Symp Nanostructures: Physics and Technology, St Petersburg, Russia. 14-18 Jun 1999. p248-251. This article is from ADA407055 Nanostructures: Physics and Technology. 7th International Symposium. St. Petersburg, Russia, June 14-18, 1999 Proceedings

The symmetry of wurtzite (GaN)(sub m) (AlN)(sub n), is established to depend on the numbers of monolayers of constituent materials in the primitive cell being C?4 to 6V! (odd m+n) or C?1 to 3V! (even m+n). As a result it was shown that the number of Raman active modes depends non-monotonically on m+n., Pres: 7th Int Symp Nanostructures: Physics and Technology, St Petersburg, Russia. 14-18 Jun 1999. p372-375. This article is from ADA407055 Nanostructures: Physics and Technology. 7th International Symposium. St. Petersburg, Russia, June 14-18, 1999 Proceedings

A quantum dot structure containing two layers of small coherent InAs clusters embedded into Si single crystal matrix was grown by MBE. The structure of these clusters was investigated by high resolution transmission electron microscopy. The quality of the grown structure severely depends on the substrate temperature growth sequence and the geometrical parameters of the sample. Investigation demonstrate that Si crystal can incorporate only a limited volume of the deposited InAs in a form of coherent clusters., Pres: 7th Int Symp Nanostructures: Physics and Technology, St Petersburg, Russia. 14-18 Jun 1999. p216-219. This article is from ADA407055 Nanostructures: Physics and Technology. 7th International Symposium. St. Petersburg, Russia, June 14-18, 1999 Proceedings

We study the effect of correlations between impurity potentials in different layers on the Coulomb drag in a double-layer semiconductor electron system. It is found that for strongly correlated potentials the drag in the diffusive regime is considerably enhanced as compared to conventional predictions. The appropriate experimental conditions are discussed, and the new experiments are suggested., Pres: 7th Int Symp Nanostructures: Physics and Technology, St Petersburg, Russia. 14-18 Jun 1999. p88-91. This article is from ADA407055 Nanostructures: Physics and Technology. 7th International Symposium. St. Petersburg, Russia, June 14-18, 1999 Proceedings

We present a new modulation technique by the control of latenil modal gain profile in four-terminal stepped-mesa diode laser. The simulation of the high frequency laser characteristics is performed on the basis of a computer model of stripe geometry diode laser which takes into account lateral effects. Modulaflon bandwidth of II GHz for ridge laser can be extended for 5 6 GHz by employing a newly developed stepped-mesa laser design. Moreover. nearly flat small signal modulation response with 3 dB bandwidth as high as 38 GHz can be obtained by making use of modulation of the lateral gain profile., Pres: 7th Int Symp Nanostructures: Physics and Technology, St Petersburg, Russia. 14-18 Jun 1999. p142-145. This article is from ADA407055 Nanostructures: Physics and Technology. 7th International Symposium. St. Petersburg, Russia, June 14-18, 1999 Proceedings

This work demonstrated room temperative CW lasing via the QD states with the maximum output power as high as 3 3 W. This result points out that QDs can be used as an active region of injection lasers for high-power applications. We believe that further progress can be achieved by optimizing both the design of active region and the fabrication of laser diodes., Pres: 7th Int Symp Nanostructures: Physics and Technology, St Petersburg, Russia, 14-18 Jun 1999. p128-130. This article is from ADA407055 Nanostructures: Physics and Technology. 7th International Symposium. St. Petersburg, Russia, June 14-18, 1999 Proceedings

Capacitance and conductance-voltage characteristics have been measured at various frequencies and temperatures for a Schottky barrier structure containing three sheets of self-organized InAs quantum dots in an n-GaAs matrix. The capacitance of the structure consists of bulk and quantum dot contributions whereas the conductance mainly depends on the electron transfer out of the dots which is a function of the balance between measurement frequency and the thermionic emission rate of carriers from quantum dots. An analysis of the temperature dependent conductance of the structure gives information about the electronic structure and electron emission rate from the quantum dots., Pres: 7th Int Symp Nanostructures: Physics and Technology, St Petersburg, Russia. 14-16 Jun 1999. p232-235. This article is from ADA407055 Nanostructures: Physics and Technology. 7th International Symposium. St. Petersburg, Russia, June 14-18, 1999 Proceedings

Ferromgnetic semiconductor heterostructures MnAs/Si(111) have been studied by using the optical second harmonic generation and the linear magneto-optical Kerr effect. Magnetic and crystallographic contributions to the SHG are separated on the base of rotational anisotropy method. Magnetic hysteresis loops measured by the SHG and the Kerr effect exhibit different behavior due to a different sensitivity Of two optical techniques to the interface surface and bulk properties., Pres: 7th Int Symp Nanostructures: Physics and Technology, St Petersburg, Russia. 14-18 Jun 1999. p228-231. This article is from ADA407055 Nanostructures: Physics and Technology. 7th International Symposium. St. Petersburg, Russia, June 14-18, 1999 Proceedings

A new metbod for the fabrication of monodisperse metallic nanostructures is described. The method is based on laser ablation of Cu target and subsequent fission of the splashed liquid Cu drops resulting from drops charging in the laser torch plasma up to instability threshold. The monodisperse charged nanoparticles produced by fission are directed to the substrate by the external electric field. The final stage of structure formation is free air oxidation of the deposited film. The structures were studied by SEM, AFM, surface profilometry. and XPS methods. It is shown that the film packed spherical Cu nanoparticles. about 6 nm in diameter covered by the Cu2O layer of the thickness of 0.8 nm. Average gap between the neighbouring nanoparticles is controlled by laser beam intensity and it can be changed from delta w = approx. 1 nm to 4 nm. The fabricated films can consist of one or several monolayers of oxidized Cu granules., Pres: 7th Int Symp Nanostructures: Physics and Technology, St Petersburg, Russia. 14-18 Jun 1999. p205-208. This article is from ADA407055 Nanostructures: Physics and Technology. 7th International Symposium. St. Petersburg, Russia, June 14-18, 1999 Proceedings

The Kadanoff Baym Keldysh nonequilibnum Greens function technique is used to study quantum transport within the lowest miniband of semiconductor superlattices (SLs) under high electric fields. Both intra-collisional field effects (ICFEs) and lifetime broadening are taken into account. An inevitable extension of the generalized Kadanoff Baym ansatz is discussed. The collisional broadening of electro-phonon resonances due to scattering on impurities is calculated. Even if the mean impurity scattering strength is considerably smaller than the miniband width, the oscillatory current anomalies. which result from ICFEs. are completely smeared out., Pres: 7th Int Symp Nanostructures: Physics and Technology, St Petersburg, Russia. 14-18 Jun 1999. p92-94. This article is from ADA407055 Nanostructures: Physics and Technology. 7th International Symposium. St. Petersburg, Russia, June 14-18, 1999 Proceedings

The new road of "rolling up" conformation of a graphite fragment into a fullerene is considered in context of the theory of the growth of carbon nanoparticles. The small curved flake-like fragments of the graphite monolayer are investigated as an intermediate step along the conformation path. The optimal shape of the clusters with the small curvature is found within the phenomenological model., Pres: 7th Int Symp Nanostructures: Physics and Technology, 14-18 Jun 1999. p543-546. This article is from ADA407055 Nanostructures: Physics and Technology. 7th International Symposium. St. Petersburg, Russia, June 14-18, 1999 Proceedings

Pres: 7th Int Symp Nanostructures: Physics and Technology, St Petersburg, Russia. 14-18 Jun 1999. This article is from ADA407055 Nanostructures: Physics and Technology. 7th International Symposium. St. Petersburg, Russia, June 14-18, 1999 Proceedings

It has been shown that the growth interruption peffomed for calibration of VI-II flux ratio leads to the additional strain contrast in cross-sectional TEM images. Futhermore, this strain seems to be the driven force for the formation of extended defects immediately at the interruption interface. On the other hand, the developed alternately-strained SLs allow one to enhance the activation energy of the development and propagation of extended defects and protect the laser active region from the defects penetration. These findings, while being qualitative, are important for further decrease of the defects density in ZnSe-based laser structures., Pres: 7th Int Symp Nanostructures: Physics and Technologies, St Petersburg, Russia. 14-18 Jun 1999. p547-549. This article is from ADA407055 Nanostructures: Physics and Technology. 7th International Symposium. St. Petersburg, Russia, June 14-18, 1999 Proceedings

We study lateral current density patterns in a double-barrier resonant tunneling structure with a bistable Z-shaped current-voltage characteristic. It is shown that for a positive load the external circuit provides a positive feedback upon the dynamics of the current pattens. This leads to accelerated motion of lateral switching fronts which switch the device from the low-conductivity to the high-conductivity state. and vice versa. Negative feedback and stabilization of a stationary front can be achieved by implementation of an active external circuit simulating a negative load., Pres: 7th Int Symp Nanostructures: Physics and Technology, St Petersburg, Russia. 14-18 Jun 1999. p280-283. This article is from ADA407055 Nanostructures: Physics and Technology. 7th International Symposium. St. Petersburg, Russia, June 14-18, 1999 Proceedings

A (Zn,Cd)(S,Se) MQW heterostructure is designed and fabricated to allowing control over the optical and electronic properties by an exposure to 488 nm Ar+ laser line. The laser-induced intermixing of elements results in a significant band edge blue shift with a moderate level of introduced defects. By controlling the light pattern on the sample surface this technique allows lateral pattering for fabricating e.g. ultra-narrow stripes or dot-like objects for optoelectronic devices., Pres: 7th Int Symp Nanostructures: Physics and Technology, St Petersburg, Russia. 14-18 Jun 1999. p533-535. This article is from ADA407055 Nanostructures: Physics and Technology. 7th International Symposium. St. Petersburg, Russia, June 14-18, 1999 Proceedings

Magneto-reflectivity has been studied in modulation doped ZnSe/ZnMgSSe quantum well structures with low and moderate carrier concentrations. Negatively charged exciton (trion) lines were observed in the reflectivity spectra. Magnetic field induced circular polarization of the trion reflection line has been found to correlate with the polarization of electron gas at filling factor nu < 2., Pres: 7th Int Symp Nanostructures: Physics and Technology, St Petersburg, Russia. 14-18 Jun 1999. p352-355. This article is from ADA407055 Nanostructures: Physics and Technology. 7th International Symposium. St. Petersburg, Russia, June 14-18, 1999 Proceedings

We report on MOCVD growth of the (In,Al)As-se1f-organized quantum dots (QD) on (Al,Ga)As. We demonstrate that dense arrays (about 2 x 10exp10/cm2) of small ( about 5 nm) QD are formed during annealing (75O C, 20 min, excess of arsine) of In(0.5)Al(0.5)As deposited at 500 C on a Al(0.6)Ga(0.4)As surface as demonstrated by atomic force and transmission electron microscopies and by photoluminescense. We determined that the opening process continues at room temperature and gives rise to large clusters of submicron size after time of one. In contrast, an identical sample that is not annealed shows low density (2 x 10exp9/cm2) of the QDs. Aging in this case gives results in a gradual smoothing of the morphology., Pres: 7th Int Symp Nanostructures: Physics and Technology, St Petersburg, Russia; 14-18 Jun 1999. p525-528. This article is from ADA407055 Nanostructures: Physics and Technology. 7th International Symposium. St. Petersburg, Russia, June 14-18, 1999 Proceedings

The InGaN alloys have acquired a lot of interest for using in the active region of light emitting and lasers diodes as the band gap of these materials can be varied over nearly the whole visible spectral range when changing In content from 0 to pure InN. However due to the low dissociation temperature of InN (about 63O C ) and the nitrogen equilibrium vapor pressure with a growth temperature (T(g)) good quality InN epilayers are still not easily attainable. Taking account of the large lattice mismatch between InN and sapphire it is also expected that a strain induced enhanced N re-evaporation at the initial InN monolayer growth would require a 100 - 150 C decrease of T(s) to avoid a liquid to droplet formation followed by a columnar structure growth. As a result there are only few papers to our knowledge on epitaxial InN properties and no reports on hexagonal InN films MBE growth., Pres: 7th Int Symp Nanostructures: Physics and Technology, St Petersburg, Russia. 14-18 Jun 1999. p521-524. This article is from ADA407055 Nanostructures: Physics and Technology. 7th International Symposium. St. Petersburg, Russia, June 14-18, 1999 Proceedings

We have performed a magnetooptical study on spin superlattice structures fabricated on the basis of (ZnMn)Se/(ZnBe)Se. The band alignment of a Zn(0.91)Mn(0.09)Se/ Zn(0.972)Be(0.028)Se superlattice was found to undergo a type-I to type-Il transition for one of the exciton spin component. This spin superlattice formation manifests itself in an asymmetric Zeeman splitting of a spatially direct exciton resulting from a spin dependent change of the exciton binding energy. A pronounced broadening of the spatially direct exciton in reflectance and photoluminescence excitation spectra was observed when scattering in the (ZnBe)Se barriers becomes possible., Pres: 7th Int Symp Nanostructures: Physics and Technology, St Petersburg, Russia. 14-18 Jun 1999. p348-351. This article is from ADA407055 Nanostructures: Physics and Technology. 7th International Symposium. St. Petersburg, Russia, June 14-18, 1999 Proceedings

The GaAs crystals are shown to lower symmetry from T(d) to D(2d) or C(2v) when inserting a delta-layer with odd or even number of Si planes respectively. These symmetry changes correspond to uniaxial or plane distoition of the GaAs lattice in the neighbourhood of a delta-layer. The band shifts of GaAs induced by the insertiOn of delta-layers are estimated., Pres: 7th Int Symp Nanostructures: Physics and Technology, St Petersburg, Russia. 14-18 Jun 1999. p295-298. This article is from ADA407055 Nanostructures: Physics and Technology. 7th International Symposium. St. Petersburg, Russia, June 14-18, 1999 Proceedings

In plane linear polarization of luminescence under above-band-gap excitation was investigated in type II and type I GaAs/AlAs (001) quantum wells and superlattices together with the study of level anticrossing and ODMR. Correlation of such polarization with the preferential exciton localization was found and discussed in terms of coexistence of excitons and separately localized electrons and holes. The influence of the substrate temperature on the interface quality was revealed in type I GaAs/AlGaAs quantum wells from level-anticrossing spectroscopy., Pres: 7th Int Symp Nanostructure: Physics and Technology, St Petersburg, Russia. 14-18 Jun 1999. p360-363. This article is from ADA407055 Nanostructures: Physics and Technology. 7th International Symposium. St. Petersburg, Russia, June 14-18, 1999 Proceedings

We report on a strong enhancement of the Pockels effect in direct-gap type-II ZnSe/BeTe heterostructures. The effect has been found experimentally and analyzed theoretically. In quantum well structures with equivalent interfaces, say the Zn-Te and Te-Zn interfaces, the unbiased sample is optically isotropic in the plane perpendicular to the growth direction. In the presence of an electric field the electron and hole wave functions are pushed towards one of the interfaces and off from the other, as a result the balance is broken and the photoluminescence polarization becomes nonzero and reaches 70-80 in moderate electric fields. To desciibe the field-induced in-plane anisotropy in type-II heterostructures, a theoretical model has been developed which is based on the representation of optical matrix elements in the microscopical tight binding model., Pres: 7th Int Symp Nanostructures: Physics and Technology, St Petersburg, Russia. 14-18 Jun 1999. p336-339. This article is from ADA407055 Nanostructures: Physics and Technology. 7th International Symposium. St. Petersburg, Russia, June 14-18, 1999 Proceedings

The theory of electron spectrum in quasiplane superlattice of cylindric quantum dots is built using the modified method of augmented plane waves. It is established that quasiplane energy bands arise only when the ratio between cylinder height and radius of base is bigger than some critical value., Pres: 7th Int Symp Nanostructures: Physics and Technology, St Petersburg, Russia. 14-18 Jun 1999. p74-76. This article is from ADA407055 Nanostructures: Physics and Technology. 7th International Symposium. St. Petersburg, Russia, June 14-18, 1999 Proceedings

Photoluminescence study (PL) of the self-assembling Stranski Krastanov growth of InP nanoscale islands embedded in In(0.49)Ga(0.51)P matrix by low pressure metal organic vapor phase epitaxy are presented. The temperature and the excitation level dependencies of the external quantum efficiency of these structures were invesflgated. InP nanoislands demonstrate a high quantum efficiency at 77 K and high PL wavelength temperature stability., Pres: 7th Int Symp Nanostructures: Physics and Technology, St Petersburg, Russia, 14-18 Jun 1999. p67-69. This article is from ADA407055 Nanostructures: Physics and Technology. 7th International Symposium. St. Petersburg, Russia, June 14-18, 1999 Proceedings

Pres: 7th Int Symp Nanostructures: Physics and Technology, St Petersburg, Russia. 14-18 Jun 1999. p435-437. This article is from ADA407055 Nanostructures: Physics and Technology. 7th International Symposium. St. Petersburg, Russia, June 14-18, 1999 Proceedings

Nanocrystalline silicon films have been produced by PECVD metbod in SiH4 t H2 gas mixtures. Raman spectral IR absorption and absorption edge of the films have been investigated in a function of such deposition parameters as the gas dilution ratio H2O contamination the deposition temperature (T(d)) and the material of the substrate. The study of IR spectra has showed the presence of bonded hydrogen, with the total concentration (CH) varying from 4 to 13 at.%. The analysis of Raman spectra has revealed that the films contain nanocrystallites embedded in amorphous matrix., Pres: 7th Int Symp Nanostructures: Physics and Technology: St Petersburg, Russia. 14-18 Jun 1999. p325-328. This article is from ADA407055 Nanostructures: Physics and Technology. 7th International Symposium. St. Petersburg, Russia, June 14-18, 1999 Proceedings

In summary we experimentally observe the increase of the PL intensity in InAs/GaAs self assembled QDs induced by subband 1.06 micron optical excitation. For low interband excitation density the relative increase reaches the value of 40%. The relative increase of PL intensity saturates at high density of subband excitation. We would like to point that the present observation may be useful in the attempts to decrease the threshold current density in QD lasers., Pres: 7th Int Symp Nanostructures: Physics and Technology; St Petersburg, Russia. 14-18 Jun 1999. p58-60. This article is from ADA407055 Nanostructures: Physics and Technology. 7th International Symposium. St. Petersburg, Russia, June 14-18, 1999 Proceedings

The oscillator strength of an exciton in a single QW is defined not only by the overlap of the electron anD hole wave functions as was believed recently, but is defined by the electromagnetic field distribution in a strUctUre as well., Pres: 7th Int Symp Nanostructures: Physics and Technologies; St Petersburg, Russia. 14-18 Jun 1999. p61-62. This article is from ADA407055 Nanostructures: Physics and Technology. 7th International Symposium. St. Petersburg, Russia, June 14-18, 1999 Proceedings

IWe studied the effect of the composition profile of pseudomorphic channel on transport properties of InGaAs/InAlAs structures. The increase in the effective separation of 2DEG from the heterointerface and the channel thickness was shown to be the key point to achieve the maximal mobility. The possibility to achieve excellent transport properties in structures with very thin InGaAs buffer layer is shown., Pres: 7th Int Symp Nanostructures: Physics and Technology, St Petersburg, Russia. 14-18 Jun 1999. p85-87. This article is from ADA407055 Nanostructures: Physics and Technology. 7th International Symposium. St. Petersburg, Russia, June 14-18, 1999 Proceedings

The International Symposium "Nanostructures: Physics and Technology" is held annually since 1993., For individual articles, see ADP012853 thru ADP013001

Pres: 6th Int Symp Nanostructures: Physics and Technology, St Petersburg, Russia. 22-26 Jun 1998. p406-409. This article is from ADA406591 Nanostructures: Physics and Technology International Symposium (6th) held in St. Petersburg, Russia on June 22-26, 1998 Proceedings

Pres: 6th Int Symp Nanostructures: Physics and Technology, St Petersburg, Russia. 22-26 Jun 1998. p395-397. This article is from ADA406591 Nanostructures: Physics and Technology International Symposium (6th) held in St. Petersburg, Russia on June 22-26, 1998 Proceedings

Quantum dot (QD) heterostructures have recently became the subject of the intensive research. tnjection lasers with an active region based on InGaAs/AlGaAs QD have shown ultralow threshold current density (J(subth)). However the emission wavelength of QDs formed on GaAs substrate is limited by the value of 1.3 microns. It has been previously shown that the QD emission range can be extended up to 2 microns by embedding the InAs QDs into an InGaAs matrix grown on InP substrate. In this work we study threshold, tempemture and power characteristics of InAs/InGaAs/InP injection lasers., Pres: 6th Int Symp Nanostructures: Physics and Technology, St Petersburg, Russia, 22 Jun 1998. p402-405. This article is from ADA406591 Nanostructures: Physics and Technology International Symposium (6th) held in St. Petersburg, Russia on June 22-26, 1998 Proceedings

6TH International Symposium held in St. Petersburg Russia on 22-26 Jun 1998., Pres: 6th International Symposium St. Petersburg, Russia, 22-26 Jun 1998. For individual articles, see ADP012712 thru ADP012852

The Zeenmn effect for 1D and 0D electron states has been considered theoretically. We have established the relation between the point symmetry of a low-dimensional system and properties of the g factor tensor g(sub alpha beta) from which, in particular, it turns out that the g factor in a cylindrical wire is isotropic (g(sub xx = g(sub yy) = g(sub zz)). The actual calculation of g( sub alpha beta) is performed for the ground states in rectangular quanturn wire, cylindrical wire and spherical quanturn dot structures., Pres: 6th Int Symp Nanostructures: Physics and Technology, St Petersburg, Russia. 22-26 Jun 1998. p222-225. This article is from ADA406591 Nanostructures: Physics and Technology International Symposium (6th) held in St. Petersburg, Russia on June 22-26, 1998 Proceedings

Capacitance and conductance voltage characteristics have been measured at various frequencies and temperatures for a Schottky barrier structure containing three sheets of self assembled InAs quantum dots in an n-GaAs matrix. By changing the temperature and the frequency of the measuring signal, it is possible to control quantum dot part of capacitance of the structure. It was shown that analysis of the admittance spectra allows us to obtain information about dynamic parameters of quantum dots., Pres: 6th Int Symp Nanostructures: Physics and Technology, St Petersburg, Russia. 22 Jun 1998. p424-427. This article is from ADA406591 Nanostructures: Physics and Technology International Symposium (6th) held in St. Petersburg, Russia on June 22-26, 1998 Proceedings

This report considered the laser diode dual modulation (by pump current and confinement factor variation) possibility to be a method to control the polarization of the laser radiation. The carried out mathematical modeling of the laser diode under the dual modulation proved the possibility of direct control of laser radiation polarization keeping the output power near to be constant., Pres: 6th Int Symp Nanostructures: Physics and Technology, St Petersburg, Russia. 22-26 Jun 1998. p417-420. This article is from ADA406591 Nanostructures: Physics and Technology International Symposium (6th) held in St. Petersburg, Russia on June 22-26, 1998 Proceedings

Optical experiments with self-organised InAs/GaAs quantum dots (QD) show high quantum efficiency of photoluminescence (PL) which is important for laser applications. However the channels of nonradiative carrier recombination which competes with PL in QDs are not understood yet. In the present contribution we study the effect of enhancement of PL quantum efficiency of InAs/GaAs QDs induced by subband 1.06 micrometer illumination., Pres: 6th Int Symp Nanostructures: Physics and Technology, St Petersburg, Russia. 22-26 Jun 1998. p226-227. This article is from ADA406591 Nanostructures: Physics and Technology International Symposium (6th) held in St. Petersburg, Russia on June 22-26, 1998 Proceedings

We have observed a strong dependence of the intensity of the ordering-induced phonon bands on thermal treatment (rapid cooling and annealing) in Ranmn spectra (RS) of CuPt(sub-B) ordered Ga(0.5)In(0.5)P alloys. The changes of the Raman intensity occur only in diagonal backscattering configuration: y'\\ 1-BAR,1,0, where the polarization of light is parallel to the mirror planes of the ordered structure. We found that there are at least two different intensity distributions of the optical phonon bands the appearance of which is determined by thermal treatment and the alloy film thickness. The bond polarizability model analysis shows that the observed RS behaviour can be described in terms of the order-disorder martensitic transition on trigonal lattice sites., Pres: 6th Int Symp Nanostructures: Physics and Technology, St Petersburg, Russia. 22 Jun 1998, p444-447. This article is from ADA406591 Nanostructures: Physics and Technology International Symposium (6th) held in St. Petersburg, Russia on June 22-26, 1998 Proceedings

The XPS-TEM study of Cu/SiO2 composite metal-insulator films allowed us to develop the diagnostics of the chemical states of metal atoms and the parameters of the ensembles of metal-clusters and metal-atoms which are important for single-electron tunnelling processes., Pres: 6th Int Symp Nanostructures: Physics and Technology; St Petersburg, Russia. 22-26 Jun 1998. p436-439. This article is from ADA406591 Nanostructures: Physics and Technology International Symposium (6th) held in St. Petersburg, Russia on June 22-26, 1998 Proceedings

Results on Cu K-edge x-ray absorption study of copper dispersed in SiO2 are reported. Randomly distributed in as-made samples at low concentration, copper atoms tends to form clusters at larger concentrations. The cluster size reaches a size of 20 to 50 A after which the cluster growth stops. Only the first-neighbour peak is observed in as-made samples indicating either a very strong disorder in clusters or their low-dimensionality. Annealing results in the formation of copper clusters of the same size with fcc structure., Pres: 6th Int Symp Nanostructures: Physics and Technology, St Petersburg, Russia. 22 Jun 1998. p440-443. This article is from ADA406591 Nanostructures: Physics and Technology International Symposium (6th) held in St. Petersburg, Russia on June 22-26, 1998 Proceedings