Band offset in GaAs/AlxGa1−xAs multiple quantum wells calculated with thesp3s*tight-binding model

The spectroscopic investigation of GaN/AlGaN quantum wells reveals that the emission energy of such structures is determined by four parameters, namely composition, well-width, strain and charge density. The experimental data obtained by varying these parameters are quantitatively explained by an analytic model based on the envelope function formalism which accounts for screening and built-in field, and by a full self-consistent tight-binding model.

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Exciton localization effects and heterojunction band offset in (Ga,In)P-(Al,Ga,In)P multiple quantum wells

Physical Review B ◽

10.1103/physrevb.47.12598 ◽

1993 ◽

Vol 47 (19) ◽

pp. 12598-12604 ◽

Cited By ~ 53

Author(s):

Martin D. Dawson ◽

Geoffrey Duggan

Keyword(s):

Quantum Wells ◽

Multiple Quantum Wells ◽

Band Offset ◽

Multiple Quantum ◽

Exciton Localization

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Influence of Internal Electric Fields on the Ground Level Emission of GaN/AlGaN Multi-Quantum Wells

MRS Proceedings ◽

10.1557/proc-595-f99w12.6 ◽

1999 ◽

Vol 595 ◽

Author(s):

A. Bonfiglio ◽

M. Lomascolo ◽

G. Traetta ◽

R. Cingolani ◽

A. Di Carlo ◽

...

Keyword(s):

Experimental Data ◽

Quantum Wells ◽

Electric Fields ◽

Tight Binding ◽

Ground Level ◽

Analytic Model ◽

Tight Binding Model ◽

Binding Model ◽

Emission Energy ◽

Self Consistent

AbstractThe spectroscopic investigation of GaN/AlGaN quantum wells reveals that the emission energy of such structures is determined by four parameters, namely composition, well-width, strain and charge density. The experimental data obtained by varying these parameters are quantitatively explained by an analytic model based on the envelope function formalism which accounts for screening and built-in field, and by a full self-consistent tight-binding model.

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TIGHT-BINDING METHOD FOR QUANTUM-CONFINEMENT ENERGY CALCULATIONS IN THE CdSe/ZnSe MULTIPLE QUANTUM WELLS

International Journal of Modern Physics C ◽

10.1142/s0129183108013175 ◽

2008 ◽

Vol 19 (11) ◽

pp. 1635-1645

Author(s):

NACIR TIT ◽

IHAB M. OBAIDAT

Keyword(s):

Quantum Wells ◽

Quantum Confinement ◽

Bound States ◽

Energy Levels ◽

Tight Binding ◽

Relevant Information ◽

Physical Models ◽

Multiple Quantum Wells ◽

Bandgap Energy ◽

Multiple Quantum

We present an efficient method to calculate the quantum-confinement energy of charge carriers in the ( ZnSe )M( CdSe )N (001) multiple quantum wells (MQW). The method is based on the 3D empirical sp3s* tight-binding models, which include the spin-orbit coupling. The method can handle large systems while it takes account of the band mixing caused by the strain and confinement. In these perspectives, it proves itself more reliable than the traditional effective-mass approach (EMA) by further generating more relevant information about the quantum states localized within the wells; in particular, the number of bound states and their energy levels and their corresponding wavefunctions were obtained based on more realistic physical models. The quantum-confinement energy, bandgap energy, and band structures are studied versus the CdSe well width (N). The results are found to be comparable with those experimentally obtained using photoluminescence.

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Resonance Modes in Multiple Quantum Wells Structure of Two-Dimensional Photonic Crystal

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.457-458.85 ◽

2012 ◽

Vol 457-458 ◽

pp. 85-88

Author(s):

Chun Mei Zhang ◽

Tao Meng ◽

Yan Ping Hao ◽

Fu Ping Liu

Keyword(s):

Photonic Crystal ◽

Quantum Wells ◽

Tight Binding ◽

Multiple Quantum Wells ◽

Square Lattice ◽

Multiple Quantum ◽

Two Dimensional ◽

Resonance Modes ◽

Frequency Split ◽

Two Dimensional Photonic Crystal

We have theoretically discussed the resonance modes in a two-dimensional photonic multiple quantum wells structure (QWs) consists of one photonic crystal with square lattice of parallel dielectric circular columns in air and some layers of columns are removed at constant intervals. The generation and frequency split of resonance modes are observed and explained with tight-binding approach. The effect of the interaction distance on the frequency split is also discussed.

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Intersubband Transitions in InxGa1-xAs/AlGaAs Multiple Quantum Wells for Long Wavelength Infrared Detection

MRS Proceedings ◽

10.1557/proc-744-m9.7 ◽

2002 ◽

Vol 744 ◽

Author(s):

Clayton L. Workman ◽

Zhiming Wang ◽

Wenquan Ma ◽

Christi E. George ◽

R. Panneer Selvam ◽

...

Keyword(s):

Quantum Wells ◽

Infrared Detector ◽

Indium Content ◽

Multiple Quantum Wells ◽

Band Offset ◽

Multiple Quantum ◽

Material System ◽

Intersubband Transitions ◽

Long Wavelength ◽

Long Wavelength Infrared

ABSTRACTWe report on intersubband transitions in InxGa1-xAs/AlGaAs multiple quantum wells (MQWs) grown by molecular beam epitaxy. The conduction band offset for this material system is larger than that of the well known GaAs/AlGaAs system, thus making it possible to design, grow, and fabricate quantum well infrared photodetectors operational beyond the 14 μm spectral region with minimized dark current. We have grown InxGa1-xAs/AlGaAs MQWs with indium compositions ranging from x = 0.08 to 0.20 verified by in situ RHEED oscillations, band offset measurements, and high-resolution X-ray diffraction. Band-to-band transitions were verified by photoluminescence measurements, and intersubband transitions were measured using Fourier transform infrared (FTIR) spectroscopy. Due to the high strain and introduction of dislocations associated with the high indium content, wells with indium compositions above ∼ 0.12 did not result in intersubband transitions at silicon doping levels of 2×1018 cm-3. A thick linear graded InxGa1-xAs buffer was grown below the MQW structures to reduce the strain and resulting dislocations. Intersubband transitions were measured in InxGa1-xAs wells with indium compositions of x = 0.20 and greater when grown on top of the linear graded buffer. In addition to these results, FTIR measurements on InGaAs/AlGaAs MQW multi-color, long-wavelength infrared detector structures are reported.

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