Pseudopotential calculations of AlSb under pressure
H Algarni1, O A Al-Hagan2, N Bouarissa3
1Department of Physics, Faculty of Science, King Khalid University, P. O. Box 9004, Abha 61413, Saudi Arabia; Research Center for Advanced Materials Science (RCAMS), King Khalid University, P. O. Box 9004, Abha 61413, Saudi Arabia.
Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
|September 22, 2017
Summary
This study explores how hydrostatic pressure affects aluminum antimonide (AlSb) semiconductor properties. Results show AlSb remains an indirect band-gap material under pressure, with potential applications in optoelectronics.
Area of Science:
- Solid State Physics
- Materials Science
- Semiconductor Physics
Background:
- Aluminum antimonide (AlSb) is a zinc-blende semiconductor with significant electronic and optical properties.
- Understanding the behavior of AlSb under hydrostatic pressure is crucial for its application in advanced electronic devices.
- Previous experimental data provides a baseline for theoretical investigations into AlSb's pressure-dependent characteristics.
Purpose of the Study:
- To investigate the hydrostatic pressure dependence of electronic and optical properties of AlSb.
- To determine the band-gap nature (direct or indirect) of AlSb under pressures up to 20 kbar.
- To provide theoretical insights for potential applications of AlSb in optoelectronic devices.
Main Methods:
- Utilized a pseudopotential approach for theoretical calculations.
- Calculated key electronic parameters, including effective masses for electrons and heavy holes.
- Determined optical properties such as refractive index and high-frequency dielectric constant.
Main Results:
- At zero pressure, calculated electron and heavy hole effective masses are 0.11m₀ and 0.38m₀, respectively.
- Refractive index and high-frequency dielectric constant were found to be 3.3289 and 11.08, respectively, aligning with experimental data.
- AlSb maintained an indirect (Γ-X) band-gap semiconductor nature across the 0-20 kbar pressure range, with a monotonic decrease in lattice parameter from 0.61355 nm to 0.60705 nm.
Conclusions:
- Hydrostatic pressure influences the electronic and optical properties of AlSb monotonically.
- AlSb remains an indirect band-gap semiconductor under the investigated pressure range.
- The findings suggest AlSb's suitability for mid-infrared lasers, detectors, and communication devices.
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