Spectral blueshift and improved luminescent properties with increasing GaSb layer thickness in InAs–GaSb type-II superlattices

We investigate on the infrared (IR) optoelectronic properties in short-period InAs/GaSb type-II superlattices (SLs) by a modified eight-band [Formula: see text] model. The electronic mini-band structures for such SLs are evaluated by the modified eight-band [Formula: see text] model, incorporating the microscopic interface effect. We find that with varying the values around 20/25 Å for the InAs/GaSb layer widths, the tunable mid-IR bandgaps can be achieved effectively. The SL bandgap from 275 to 346 meV can be achieved by decreasing the InAs layer thickness from 23 to 17 Å at a fixed GaSb layer thickness of 24 Å, or from 254 to 313 meV by increasing the GaSb layer thickness from 18 to 27 Å at a fixed InAs layer thickness of 21 Å. Correspondingly the optical absorptions in such systems can be tuned evidently. Our theoretical results are in good agreement with experimental data over a series of SL samples. This study confirms further that short-period InAs/GaSb type-II SLs are of great importance for IR applications.

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Structural and optical characterization of InAs/GaSb type-II superlattices: Influence of the change in InAs and GaSb layer thicknesses for fixed InSb-like interfaces

Thin Solid Films ◽

10.1016/j.tsf.2015.07.020 ◽

2015 ◽

Vol 589 ◽

pp. 813-816 ◽

Cited By ~ 2

Author(s):

Bulent Arikan ◽

Melih Korkmaz ◽

Bulent Aslan ◽

Uğur Serincan

Keyword(s):

Optical Characterization ◽

Type Ii ◽

Gasb Layer ◽

Type Ii Superlattices

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THE REALIZATION OF TERAHERTZ BAND-GAP FROM InAs/GaSb TYPE II SUPERLATTICES

International Journal of Modern Physics B ◽

10.1142/s0217979211100199 ◽

2011 ◽

Vol 25 (07) ◽

pp. 1021-1028

Author(s):

L. L. LI ◽

H. M. DONG ◽

W. XU ◽

Y. L. SHI

Keyword(s):

Optical Absorption ◽

Band Gap ◽

High Temperatures ◽

Heavy Hole ◽

Type Ii ◽

Fundamental Band ◽

Typical Sample ◽

Gasb Layer ◽

Terahertz Band ◽

Type Ii Superlattices

We demonstrate theoretically that terahertz (THz) fundamental band-gap between the electron mini-band in the InAs layer and the heavy-hole mini-band in the GaSb layer can be realized in InAs/GaSb -based type II superlattices (SLs). The THz band-gap can be tuned by varying the widths of the InAs/GaSb layers. The presence of such band-gap can result in a strong cut-off on optical absorption at THz frequencies. For typical sample structures, the THz cut-off of the optical absorption depends sensitively on temperature and a sharper cut-off can be observed at relatively high temperatures. This study is pertinent to the application of InAs/GaSb type II SLs as THz photodetectors.

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AlSb and InAs-GaSb layer thickness effect on HH-LH splitting and band gap energies in InAs/AlSb/GaSb type-II superlattices

Opto-Electronics Review ◽

10.1515/oere-2015-0001 ◽

2015 ◽

Vol 23 (1) ◽

Cited By ~ 1

Author(s):

M.M. Alyoruk ◽

Y. Ergun ◽

M. Hostut

Keyword(s):

Band Gap ◽

Layer Thickness ◽

Heavy Hole ◽

Auger Recombination ◽

Light Hole ◽

Recombination Process ◽

Thickness Effect ◽

Type Ii ◽

Type Ii Superlattice ◽

Gasb Layer

AbstractThis study is based on the investigation of AlSb layer thickness effect on heavy−hole light−hole (HH−LH) splitting and band gap energies in a recently developed N−structure based on InAs/AlSb/GaSb type II superlattice (T2SL) p−i−n photodetector.eFirst principle calculations were carried out tailoring the band gap and HH−LH splitting energies for two possible interface transition alloys of InSb and AlAs between InAs and AlSb interfaces in the superlattice. Results show that AlSb and InAs−GaSb layer thicknesses enable to control HH−LH splitting energies to desired values for Auger recombination process where AlSb/GaSb total layer thickness is equal to InAs layers for the structures with InSb and AlAs interfaces.

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