scholarly journals ASSESSMENT OF A MULTIPLE QUANTUM WELL AND A SUPERLATTICE STRUCTURE BY SPECTROSCOPIC ELLIPSOMETRY, ELECTROREFLECTANCE AND PHOTOREFLECTANCE MODULATION SPECTROSCOPY

1987 ◽  
Vol 48 (C5) ◽  
pp. C5-139-C5-142
Author(s):  
M. ERMAN ◽  
C. ALIBERT ◽  
J. A. CAVAILLÈS ◽  
P. FRIJLINK ◽  
C. BOUCHE
Keyword(s):  
Quantum Well ◽  
Spectroscopic Ellipsometry ◽  
Multiple Quantum Well ◽  
Multiple Quantum ◽  
Modulation Spectroscopy ◽  
Superlattice Structure

Investigation of doped multiple quantum well structures using modulation spectroscopy

1994 ◽  
Author(s):  
Rudiger Goldhahn ◽  
Gerhard Gobsch ◽  
J. Martyn Chamberlain ◽  
Mohamed Henini ◽  
Andrzej F. Jezierski ◽  
...  
Keyword(s):  
Quantum Well ◽  
Multiple Quantum Well ◽  
Multiple Quantum ◽  
Modulation Spectroscopy ◽  
Quantum Well Structures

Characterization of an Asymmetric Triangular Multiple Quantum Well, by Variable Angle Spectroscopic Ellipsometry

1989 ◽  
Vol 160 ◽  
Author(s):  
Craig M. Herzinger ◽  
Paul G. Snyder ◽  
John A. Woollam ◽  
Keith Evans ◽  
C.E. Stutz ◽  
...  
Keyword(s):  
Quantum Well ◽  
Dielectric Function ◽  
Spectroscopic Ellipsometry ◽  
Multiple Quantum Well ◽  
Gaas Layer ◽  
Multiple Quantum ◽  
Bulk Gaas ◽  
Variable Angle ◽  
Variable Angle Spectroscopic Ellipsometry

AbstractVariable angle spectroscopic ellipsometry (VASE) was used to characterize a 20 period GaAs/Al(x)Ga(1-x)As multiple quantum well structure, grown by molecular beam epitaxy. The barriers were nominally 200 Å Al(.25)Ga(.75)As, and the well regions were grown to approximate a linearly graded composition, from x=0 to x=0.25, with total well width 200 Å. VASE data in the E1, E1,+Δ1. region were analyzed using four different models. It was founcЃ that the dielectric function of the cap GaAs layer was shifted to higher energy with respect to the bulk GaAs dielectric function.

The performance enhancement of an InGaN/GaN multiple-quantum-well solar cell by superlattice structure

2017 ◽  
Vol 56 (11) ◽  
pp. 110305 ◽  
Author(s):  
Hengsheng Shan ◽  
Bin Chen ◽  
Xiaoya Li ◽  
Zhiyu Lin ◽  
Shengrui Xu ◽  
...  
Keyword(s):  
Solar Cell ◽  
Quantum Well ◽  
Performance Enhancement ◽  
Multiple Quantum Well ◽  
Multiple Quantum ◽  
Superlattice Structure

RESONANT TUNNELING STUDIES OF VARIABLY SPACED MULTIPLE QUANTUM WELL STRUCTURES IN THE AlGaAs SYSTEM

1987 ◽  
Vol 48 (C5) ◽  
pp. C5-457-C5-461
Author(s):  
C. J. SUMMERS ◽  
K. F. BRENNAN ◽  
A. TORABI ◽  
H. M. HARRIS ◽  
J. COMAS
Keyword(s):  
Quantum Well ◽  
Resonant Tunneling ◽  
Multiple Quantum Well ◽  
Multiple Quantum ◽  
Quantum Well Structures

Low-Temperature Operation of Green, Blue and UV InGaN/GaN Multiple-Quantum-Well Light-Emitting Diodes

2003 ◽  
Vol 764 ◽  
Author(s):  
X. A. Cao ◽  
S. F. LeBoeuf ◽  
J. L. Garrett ◽  
A. Ebong ◽  
L. B. Rowland ◽  
...  
Keyword(s):  
Quantum Well ◽  
Light Emitting Diodes ◽  
Multiple Quantum Well ◽  
Light Output ◽  
Localized States ◽  
Multiple Quantum ◽  
Nonradiative Recombination ◽  
Light Emitting ◽  
Temperature Range ◽  
Green Leds

Absract:Temperature-dependent electroluminescence (EL) of InGaN/GaN multiple-quantum-well light-emitting diodes (LEDs) with peak emission energies ranging from 2.3 eV (green) to 3.3 eV (UV) has been studied over a wide temperature range (5-300 K). As the temperature is decreased from 300 K to 150 K, the EL intensity increases in all devices due to reduced nonradiative recombination and improved carrier confinement. However, LED operation at lower temperatures (150-5 K) is a strong function of In ratio in the active layer. For the green LEDs, emission intensity increases monotonically in the whole temperature range, while for the blue and UV LEDs, a remarkable decrease of the light output was observed, accompanied by a large redshift of the peak energy. The discrepancy can be attributed to various amounts of localization states caused by In composition fluctuation in the QW active regions. Based on a rate equation analysis, we find that the densities of the localized states in the green LEDs are more than two orders of magnitude higher than that in the UV LED. The large number of localized states in the green LEDs are crucial to maintain high-efficiency carrier capture at low temperatures.

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