MAGNETO-LUMINESCENCE OF A SINGLE LATERAL ISLAND FORMED IN A TYPE - II GaAs/AlAs QW

Ensembles of sharp emission lines present in the macro-luminescence of type-II GaAs / AlAs double quantum well structures were studied. Micro-luminescence experiments allowed us to conclude that the sharp emission lines originate from lateral GaAlAs islands of a few μm in diameter, formed in the structure. They serve as efficient type-I recombination centers for indirect excitons and/or carriers diffusing in the GaAs / AlAs QW structure. Magneto-luminescence spectra from single islands resemble those observed for natural quantum dots formed in narrow GaAs quantum wells. The observed emission is assigned to the recombination of neutral excitons as well as excitonic molecules.

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A THEORETICAL AND EXPERIMENTAL STUDY OF ELECTRONIC CONFINEMENT, COUPLING, AND TRANSLAYER INTERACTION IN NOBLE-METAL QUANTUM-WELL STRUCTURES

Modern Physics Letters B ◽

10.1142/s0217984994001084 ◽

1994 ◽

Vol 08 (18) ◽

pp. 1075-1096 ◽

Cited By ~ 3

Author(s):

W. E. MCMAHON ◽

T. MILLER ◽

T.-C. CHIANG

Keyword(s):

Quantum Well ◽

Quantum Wells ◽

Noble Metal ◽

Experimental Studies ◽

Surface States ◽

Double Quantum ◽

Multilayer Systems ◽

Quantum Well Structures ◽

Double Quantum Well ◽

Bloch Electrons

Noble-metal multilayer systems have been grown and examined with angle-resolved photoemission. Surface states, and single and double quantum wells have been studied experimentally; the results can be explained with a simple theoretical model based upon Bloch electrons. In this paper, we will present our model and then give a description of some experimental studies which utilize the model. In particular, we will consider double-quantum-well systems which can be used to examine basic aspects of electronic confinement, layer–layer coupling, and translayer interaction through a barrier.

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1.95 μm Compressively Strained Ingaas/Ingaasp Quantum Well DFB Laser With Low Threshold

MRS Proceedings ◽

10.1557/proc-484-643 ◽

1997 ◽

Vol 484 ◽

Cited By ~ 1

Author(s):

Jie Dong ◽

Akinoi Ubukata ◽

Koh Matsumoto

Keyword(s):

Quantum Well ◽

Quantum Wells ◽

Chemical Vapor ◽

Double Quantum ◽

Maximum Output ◽

Quantum Well Structures ◽

Double Quantum Well ◽

Different Temperatures ◽

Dfb Laser ◽

Strained Quantum Well

AbstractIn this study, we demonstrate the growth of highly compressively strained InGaAs/JnGaAsP quantum well structures with large well thiclmess by low pressure metalorganic chemical vapor deposition for extending the emission wavelength of lasers. By comparing the photolumineswnce characteristics of quantum wells grown at different temperatures, it is clarified that a relatively high quality quantum well layer emittig at 2.0 μ, can be obtained at a growth temperature of 650°C. 1.95-μm-wavelength InGaAs/InGaAsP highly compressively strained quantum well DFB laser for laser spectroscopy monitors was also fabricated. Double quantum-well DFB laser operating at 1.95 μm exhibits threshold currents as low as 6 mA and 6.2 mW maximum output powers. 2.04-μm-wavelength DFB laser is also described.

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Chemical Imaging of InGaAs/InAiAs Quantum Wells

MRS Proceedings ◽

10.1557/proc-466-57 ◽

1996 ◽

Vol 466 ◽

Author(s):

G. Mountjoy ◽

P. A. Crozier ◽

P. L. Fejes ◽

R. K. Tsui ◽

G. D. Kramer

Keyword(s):

Electron Microscope ◽

High Resolution ◽

Quantum Wells ◽

Chemical Imaging ◽

Double Quantum ◽

Quantum Well Structures ◽

Double Quantum Well ◽

Transmission Electron ◽

Inp Substrate ◽

Compositional Variations

ABSTRACTWe have applied high resolution chemical imaging in a transmission electron microscope to study compositional variations across InGaAs/InAIAs double quantum well structures. The structures of interest are grown on an InP substrate and consist of two 40 Å layers of InGaAs separated by 20 Å of InAlAs. For this (InGa)x(InAl)1-xAs system, we have been able to obtain compositional information with an accuracy of about 20 % and a maximum spatial resolution of 1/2 × 1/2 unit cell. The results clearly show irregularities on a monatomic scale.

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MOCVD Growth and Characterization of GaInNAs/GaAs/InGaAs/GaAs Quantum Well Structures

MRS Proceedings ◽

10.1557/proc-744-m8.16 ◽

2002 ◽

Vol 744 ◽

Author(s):

Abdel-Rahman A. El-Emawy ◽

Hongjun Cao ◽

Noppadon Nuntawong ◽

Chiyu Liu ◽

Marek Osiński

Keyword(s):

Quantum Well ◽

Quantum Wells ◽

Growth Parameters ◽

Multiple Quantum Well ◽

Double Quantum ◽

Multiple Quantum ◽

Quantum Well Structures ◽

Mocvd Growth ◽

Double Quantum Well ◽

Wavelength Emission

ABSTRACTEffects of MOCVD growth parameters on structural and optical properties of double-quantum-well (DQW) structures containing uncoupled GaInNAs/GaAs and InGaAs/GaAs quantum wells have been investigated. By varying growth temperature, growth rate, V/III ratio, and DMHy flow rates, we have achieved a longer-wavelength emission from a GaInNAs well than from an InGaAs well grown in the same structure. GaInNAs/GaAs multiple-quantum-well structures grown under optimum conditions emitted at 1.25 μm.

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GIANT INCREASE OF THE EXCITON LIFETIME IN SEMIMAGNETIC SEMICONDUCTORS WITH DOUBLE QUANTUM WELLS IN MAGNETIC FIELD

International Journal of Nanoscience ◽

10.1142/s0219581x04002358 ◽

2004 ◽

Vol 03 (04n05) ◽

pp. 541-547

Author(s):

I. Yu. GOLINEY ◽

S. B. LEV ◽

V. I. SUGAKOV ◽

G. V. VERTSIMAKHA

Keyword(s):

Magnetic Field ◽

Quantum Well ◽

Quantum Wells ◽

Double Quantum ◽

Quantum Well Structures ◽

Indirect Exciton ◽

Exciton Lifetime ◽

Double Quantum Well ◽

Single Well ◽

Semimagnetic Semiconductors

Magnetic field dependence of the excitonic spectrum and the intensity of the optical transitions for excitons in the double quantum well heterostructures based on semimagnetic semiconductors of various compositions are studied. The calculations carried out for (Zn, Mn)Se -based double quantum well structures showed that in the weak magnetic fields, the lowest energy states are the single-well states (direct excitons) for which both the electron and the hole are predominantly localized in the same well. At some values of magnetic field, the crossing of the direct exciton with indirect exciton formed by an electron and a hole, situated predominantly in the different wells, occurs. In the magnetic field exceeding some critical value, the lowest energy level belongs to the indirect exciton. According to the estimates, the lifetime of the indirect exciton is by several orders of magnitude larger than that of a single-well exciton. The exciton lifetime depends significantly on the width and the material of the barrier between the wells.

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Direct and indirect excitons in diluted magnetic semiconductor double-quantum-well structures in external magnetic fields

Journal of Physics Condensed Matter ◽

10.1088/0953-8984/16/23/020 ◽

2004 ◽

Vol 16 (23) ◽

pp. 4033-4044 ◽

Cited By ~ 4

Author(s):

S B Lev ◽

V I Sugakov ◽

G V Vertsimakha

Keyword(s):

Magnetic Fields ◽

Quantum Well ◽

Diluted Magnetic Semiconductor ◽

Magnetic Semiconductor ◽

Double Quantum ◽

Quantum Well Structures ◽

Indirect Excitons ◽

Double Quantum Well ◽

Diluted Magnetic

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ELECTRON-PHONON INTERACTIONS IN INTERSUBBAND LASER HETEROSTRUCTURES

International Journal of High Speed Electronics and Systems ◽

10.1142/s0129156402001873 ◽

2002 ◽

Vol 12 (04) ◽

pp. 939-968 ◽

Cited By ~ 3

Author(s):

Mikhail V. Kisin ◽

Mitra Dutta ◽

Michael A. Stroscio

Keyword(s):

Quantum Well ◽

Semiconductor Lasers ◽

Comprehensive Analysis ◽

Double Quantum ◽

Type I ◽

Type Ii ◽

Scattering Rate ◽

Laser Heterostructures ◽

Double Quantum Well ◽

Electron Relaxation

We present a simple semianalytical model, which allows comprehensive analysis of the LO-phonon assisted electron relaxation in quantum well intersubband semiconductor lasers. Examples of scattering rate tailoring in type-I double quantum well heterostructures and analysis of the subband depopulation process in type-II heterostructures illustrate applicability of the model.

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