Strong blue shift of the luminescence of indirect AlAs/GaAlAs quantum wells with excitation intensity

ABSTRACTPhotol uminescence of p-P InAs/InAsPSb and InAs/InAl AsSb heterojunctions grown by LPE method was studied at liquid helium temperature. The recombination spectra contained a new broad band lying between the substrate and the layer lines which was identified as an emission from the interface. This line is characterized by a strong blue shift when the excitation intensity increases. The intensities of bulk and interface lines show an unusual dependence on the pumping power. On the basis of experimental findings the interface line is attributed to emission from electrons confined at the interface due to reflection of elecctrons moving above the barrier.

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Luminescent Characteristics of InGaAsP/InP Multiple Quantum Well Structures by Impurity-Free Vacancy Disordering

MRS Proceedings ◽

10.1557/proc-692-h1.1.1 ◽

2001 ◽

Vol 692 ◽

Author(s):

J. Zhao ◽

X. D. Zhang ◽

Z. C. Feng ◽

J. C. Deng ◽

P. Jin ◽

...

Keyword(s):

Quantum Wells ◽

Band Gap ◽

Annealing Temperature ◽

Multiple Quantum Well ◽

Blue Shift ◽

Multiple Quantum ◽

Quantum Well Structures ◽

Cladding Layer ◽

Cap Layer ◽

Free Vacancy

AbstractInGaAsP/InP multiple quantum wells have been prepared by Impurity-Free Vacancy Disordering (IFVD). The luminescent characteristics was investigated using photoluminescence (PL) and photoreflectance (PR), from which the band gap blue shift was observed. Si3N4, SiO2 and SOG were used for the dielectric layer to create the vacancies. All samples were annealed by rapid thermal anne aling (RTA). The results indicate that the band gap blue shift varies with the dielectric layers and annealing temperature. The SiO2 capping was successfully used with an InGaAs cladding layer to cause larger band tuning effect in the InGaAs/InP MQWs than the Si3N4 capping with an InGaAs cladding layer. On the other hand, samples with the Si3N4-InP cap layer combination also show larger energy shifts than that with SiO2-InP cap layer combination.

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Optical Study of Bandedge Blue-Shift in AlGaN/GaN Double Quantum Wells

Chinese Physics Letters ◽

10.1088/0256-307x/14/9/019 ◽

1997 ◽

Vol 14 (9) ◽

pp. 708-711

Author(s):

Yang Kai ◽

Shen Bo ◽

Zhang Rong ◽

Zhou Yu-gang ◽

Chen Zhi-zhong ◽

...

Keyword(s):

Quantum Wells ◽

Blue Shift ◽

Double Quantum ◽

Optical Study

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Blue Shifting of Hydrogenated Silicon Carbide Multiple Quantum Wells

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.480-481.629 ◽

2011 ◽

Vol 480-481 ◽

pp. 629-633

Author(s):

Wen Teng Chang ◽

Yu Ting Chen ◽

Chung Chin Kuo

Keyword(s):

Silicon Carbide ◽

Quantum Wells ◽

Quantum Confinement Effect ◽

Chemical Vapor ◽

Blue Shift ◽

Multiple Quantum Wells ◽

Multiple Quantum ◽

Plasma Chemical ◽

Hydrogenated Silicon ◽

Plasma Chemical Vapor Deposition

Five-period hydrogenated silicon carbide (SiC) multiple quantum wells with silicon dioxide (SiO2) or silicon nitride (SiN) dielectric that were synthesized by high density plasma chemical vapor deposition were studied using photoluminescence (PL) spectroscopy to understand its blue shift. Rapid thermal annealing induced significant blue shifting in the PL spectra after fluorine ion implantation due to crystallization. The thinning of the SiC causes blue shift due to the quantum confinement effect. The higher PL intensity of the amorphous SiC:H in SiO2 than in SiC/SiN may be attributed to the high number of non-radiative sites on its surface. Annealing with nitrogen may cause impurities in SiC/SiO2, thereby broadening the PL peak.

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Effect of Thermal Annealing on the Photoluminescence Properties of a GaInNAs/GaAs Single Quantum Well

MRS Proceedings ◽

10.1557/proc-639-g6.3 ◽

2000 ◽

Vol 639 ◽

Author(s):

Laurent Grenouillet ◽

Catherine Bru-Chevallier ◽

Gérard Guillot ◽

Philippe Gilet ◽

Philippe Ballet ◽

...

Keyword(s):

Quantum Well ◽

Thermal Annealing ◽

Low Temperatures ◽

Blue Shift ◽

Emission Peak ◽

Single Quantum ◽

Photoluminescence Properties ◽

Single Quantum Well ◽

Peak Energy ◽

Strong Blue Shift

ABSTRACTWe report on the effect of thermal annealing on the photoluminescence properties of a Ga0.65In0.35N0.02As0.98/GaAs single quantum well. Thermal annealing is shown to decrease the strong nitrogen-induced localization effects observed at low temperatures and to reduce the full width at half maximum of the emission peak. It also induces a strong blue shift of the emission peak energy, which is thought not to arise from an In-Ga interdiffusion alone, as it is much larger than in a nitrogen-free reference single quantum well.

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TEMPERATURE DEPENDENCE OF PHOTOLUMINESCENCE OF FLAT AND UNDULATED SiGe/Si MULTIPLE QUANTUM WELLS

International Journal of Modern Physics B ◽

10.1142/s0217979202015108 ◽

2002 ◽

Vol 16 (28n29) ◽

pp. 4211-4214 ◽

Cited By ~ 3

Author(s):

B. W. CHENG ◽

J. G. ZHANG ◽

Y. H. ZUO ◽

R. W. MAO ◽

C. J. HUANG ◽

...

Keyword(s):

Elevated Temperature ◽

Quantum Wells ◽

Blue Shift ◽

Band Alignment ◽

Multiple Quantum Wells ◽

Luminescence Spectra ◽

Multiple Quantum ◽

Type Ii ◽

Thermally Activated ◽

Strained Sige

Photoluminescence (PL) of strained SiGe/Si multiple quantum wells (MQW) with flat and undulated SiGe well layers was studied at different temperature. With elevated temperature from 10K, the no-phonon (NP) peak of the SiGe layers in the flat samples has firstly a blue shift due to the dominant transition converting from bound excitons (BE) to free excitons (FE), and then has a red shift when the temperature is higher than 30K because of the narrowing of the band gap. In the undulated sample, however, monotonous blue shift was observed as the temperature was elevated from 10 K to 287 K. The thermally activated electrons, confined in Si due to type-II band alignment, leak into the SiGe crest regions, and the leakage is enhanced with the elevated temperature. It results in a blue shift of the SiGe luminescence spectra.

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Depth Profile of the Excitonic Luminescence in Gallium-Nitride Layers

MRS Proceedings ◽

10.1557/proc-449-677 ◽

1996 ◽

Vol 449 ◽

Cited By ~ 8

Author(s):

H. Siegle ◽

A. Hoffmann ◽

L. Eckey ◽

C. Thomsen ◽

T. Detchprohm ◽

...

Keyword(s):

Gallium Nitride ◽

Depth Profile ◽

Vapor Phase ◽

Blue Shift ◽

Peak Position ◽

Hydride Vapor Phase Epitaxy ◽

Spatially Resolved ◽

Nitride Layers ◽

Excitonic Luminescence ◽

Strong Blue Shift

ABSTRACTWe present results of spatially-resolved photoluminescence and Raman measurements on a 200 μm thick GaN layer grown on sapphire by hydride vapor phase epitaxy. Our microphotoluminescence measurements reveal that the peak position of the excitonic and donoracceptor-pair transitions strongly depends on the distance to the substrate interface. We observed a strong blue shift near the interface and discuss the influence of strain, which we quantified by micro-Raman experiments.

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1.37 - 2.90 Micron Intersubband Transitions in GaN/AlN Superlattices

MRS Proceedings ◽

10.1557/proc-0955-i13-01 ◽

2006 ◽

Vol 955 ◽

Author(s):

Eric Anthony DeCuir ◽

Emil Fred ◽

Omar Manasreh ◽

Jinqiao Xie ◽

Hadis Morkoc ◽

...

Keyword(s):

Quantum Wells ◽

Bound States ◽

Energy Levels ◽

Three Dimensional ◽

Blue Shift ◽

Bound State ◽

Peak Position ◽

Multiple Quantum ◽

Intersubband Transitions ◽

Photovoltaic Mode

ABSTRACTIntersubband transitions in the spectral range of 1.37-2.90 °Cm is observed in molecular beam epitaxy grown Si-doped GaN/AlN multiple quantum wells using a Fourier-transform spectroscopy technique. A blue shift in the peak position of the intersubband transition is observed as the well width is decreased. A sample with a well width in the order of 2.4 nm exhibited the presence of three bound states in the GaN well. The bound state energy levels are calculated using a transfer matrix method. An electrochemical capacitance voltage technique is used to obtain the three dimensional carrier concentrations in these samples which further enable the calculation of the Fermi energy level position. Devices fabricated from these GaN/AlN quantum wells are found to operate in the photovoltaic mode.

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