Author: E. E. MendezPublisher:
ISBN:
Category :
Languages : en
Pages : 5
Book Description
Effect of an Electric Field on the Luminescence of GaAs Quantum Wells
Author: E. E. MendezOptical Effect of Electric Field on Indirect Exciton Luminescence in Double Quantum Wells of GaAs
Author: V. V. KrivolapchukPublisher:
ISBN:
Category :
Languages : en
Pages : 4
Book Description
The present report studies the IX line shape in photoluminescence (PL) spectra originating from the DQW of GaAs depending on the electric field value applied to the structure. We observe unusual IX line shape behaviour in the definite range of bath temperatures and pumping intensities and discuss our results in terms of possible revealing of the collective excitations in a dense IX gas which were previoulsly predicted.
Physics and Applications of Quantum Wells and Superlattices
Author: E.E. MendezPublisher: Springer Science & Business Media
ISBN: 1468454781
Category : Science
Languages : en
Pages : 456
Book Description
This book contains the lectures delivered at the NATO Advanced Study Institute on "Physics and Applications of Quantum Wells and Superlattices", held in Erice, Italy, on April 21-May 1, 1987. This course was the fourth one of the International School of Solid-State Device Research, which is under the auspices of the Ettore Majorana Center for Scientific Culture. In the last ten years, we have seen an enormous increase in re search in the field of Semiconductor Heterostructures, as evidenced by the large percentage of papers presented in recent international conferences on semiconductor physics. Undoubtfully, this expansion has been made possible by dramatic advances in materials preparation, mostly by molecular beam epitaxy and organometallic chemical vapor deposition. The emphasis on epitaxial growth that was prevalent at the beginning of the decade (thus, the second course of the School, held in 1983, was devoted to Molecular Beam Epitaxy and Heterostructures) has given way to a strong interest in new physical phenomena and new material structures, and to practical applications that are already emerging from them.
Novel Electric-Field Effects in Quantum Wells, Superlattices, and Microcavities
Author: Publisher:
ISBN:
Category :
Languages : en
Pages : 0
Book Description
We have used an external electric field to control important properties of semiconductor quantum wells. Specifically: (1) We have modified the exciton-exciton interaction. This interaction is determined by many-body effects, which depend on the overlap between the exciton's electron and hole wavefunctions, and is manifested in the energy difference between photoluminescence spectra with different polarizations. In time-resolved photoluminescence (PL) experiments with circular polarization we have observed that spectral difference, which we controlled by an electric field applied to GaAs-GaAlAs coupled quantum wells. Our results confirm the predictions of theory but also point out its limitations to fully explain our observations. (2) We have reversed the valence-band ordering in strained-layer quantum wells, thus 'undoing' the effects of strain. To prove the concept we have used strained InGaAs-InAlAs quantum wells in which the light-hole state is the ground state in the valence band. Photocurrent measurements under various fields have shown a change in the valence-band states that contribute to the fundamental (lowest-energy) transition, from light-hole states to heavy-hole states. This result opens the door to reversing the polarization of light emission in quantum wells, from TM to TE, which could find application in optical modulators. (3) We have shown the presence of low-temperature exciton-photon coupling in microcavities using PL spectroscopy. Because of thermalization until now it has been almost impossible to use PL to study at low temperature (T = 20K or less) the coupling of excitons and photons. We have determined the difference between the lowest-energy PL peak from a quantum well-microcavity system and that of an isolated quantum well, at various temperatures. This difference is constant with T when a field is applied but is T dependent when the field is suppressed. The maximum variation is a direct measure of the exciton-photon coupling.
Research in Progress
Author: New Horizons in Low-Dimensional Electron Systems
Author: H. AokiPublisher: Springer Science & Business Media
ISBN: 9401131902
Category : Science
Languages : en
Pages : 471
Book Description
In Bird of Passage by Rudolf Peierls, we find a paragraph in which he de scribes his Cambridge days in the 1930s: On these [relativistic field theory] problems my main contacts were Dirac, and the younger theoreticians. These included in particular Nevill (now Sir Nevill) Mott, perhaps the friendliest among many kind and friendly people we met then. Professor Kamimura became associated with Sir Rudolf Peierls in the 1950s, when he translated, with his colleagues, Peierls's 1955 textbook, Quantum Theory of Solids, into Japanese. This edition, to which Sir Rudolf himself contributed a preface, benefitted early generations of Japanese solid state physicists. Later in 1974/5, during a sabbatical year spent at the Cavendish Laboratory, Professor Kamimura met and began a long association with Sir Nevill Mott. In particular, they developed ideas for disordered systems. One of the outcomes is a paper coauthored by them on ESR-induced variable range hopping in doped semiconductors. A series of works on disordered systems, together with those on two-dimensional systems, have served as building blocks for Physics of Interacting Electrons in Disordered Systems, in the International Series of Monographs on Physics, coauthored by Aoki and published in 1989 by the Oxford University Press. Soon after Professor Kamimura obtained a D. Sc. in 1959 for the work on the ligand field theory under the supervision ofMasao Kotani, his strong con nections in the international physical community began when he worked at the Bell Telephone Laboratories in 1961/64.
Electric Field-Induced Quenching of Luminescence in Quantum Wells
Author: E. E. MendezSuperlattices and Other Heterostructures
Author: Eougenious L. IvchenkoPublisher: Springer Science & Business Media
ISBN: 3642606504
Category : Technology & Engineering
Languages : en
Pages : 396
Book Description
Superlattices and Other Heterostructures deals with optical properties of superlattices and quantum-well structures with emphasis on phenomena governed by crystal symmetries. After a brief introduction to group theory and symmetries, methods to calculate spectra of electrons, excitions and phonons in heterostructures are discussed. Further chapters cover absorption and reflection of light under interband transitions, cyclotron and electron spin-resoncance, light scattering by free and bound carriers as well as by optical and acoustic phonons, polarized photoluminescence, optical spin orientation of electrons and excitions, and nonlinear optical and photogalvanic effects.
Electronic Structure of Semiconductor Heterojunctions
Author: Giorgio MargaritondoPublisher: Springer Science & Business Media
ISBN: 9400930739
Category : Science
Languages : en
Pages : 348
Book Description
E se non che di cid son vere prove A nd were it not for the true evidence Per piti e piti autori, che sa, ra. nno Of many authors who will be Per i miei versi nominati altrove, Mentioned elsewhere in my rhyme Non presterei alla penna 10. mana I would not lend my hand to the pen Per nota1' cid ch'io vidi, can temenza And describe my observations, for fear ehe non fosse do. altri casso e van 0; That they would be rejected and in vane; Mala lor chiara. e vera. esperienza But these authors' clear and true experience Mi assicura. nel dir, come persone Encourages me to report, since they Degne di fede ad ogni gra. n sentenza. Should always be trusted for their word. [From" Dittamondo", by Fazio degli UbertiJ Heterojunction interfaces, the interfaces between different semiconducting materi als, have been extensively explored for over a quarter of a century. The justifica tion for this effort is clear - these interfaces could become the building blocks of lllany novel solid-state devices. Other interfaces involving semiconductors are al ready widely used in technology, These are, for example, metal-semiconductor and insulator-semiconductor junctions and hOll1ojunctions. In comparison, the present applications of heterojunction int. erfaces are limited, but they could potentially becOlne lnuch lllore ext. ensive in the neal' future. The path towards the widespread use of heterojunctions is obstructed by several obstacles
Semiconductor Superlattices
Author: M. A. HermanPublisher: Walter de Gruyter GmbH & Co KG
ISBN: 3112761855
Category : Technology & Engineering
Languages : en
Pages : 272
Book Description
No detailed description available for "Semiconductor Superlattices".