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Title: Infrared absorption spectrum of free carriers in polar semiconductors. Progress report, July 1, 1979-June 30, 1980

Abstract

The Drude Zener theory of the absorption of high frequency radiation by free carriers (inverse bremsstrahlung) has been extended into the quantum region (h-bar omega > k/sub 0/T) in terms of a frequency dependent relaxation time which predicts the dc mobility in the quasiclassical limit. Numerical calculations of the frequency and concentration dependent electron scattering rate have been completed for InP, InAs, Ga/sub 0/ /sub 47/In/sub 0/ /sub 53/As, and previous results for GaAs extended to high carrier concentrations. When starting from a quantum statistical theory, the fact that n/sub q/oh-bar omega ..-->.. k/sub 0/T at low frequencies can be used to prevent the divergence of the coulomb scattering rate without inclusion of a screening radius. A result containing no adjustable parameters is found which predicts a mobility for uncompensated samples that decreases strongly at high concentrations. This has been observed in GaAs, and is not accounted for by the usual dc calculation which assumes h-bar omega = 0 and a screening parameter. Calculated results for GaAs are in good agreement with experimental measurements of the mobility which are found to be independent of a wide variety of conditions of material preparation. This indicates that disagreement with previous theoretical calculationsmore » was not due to compensation. Calculations for ZnSe and further investigation of the modification of the optical constants by the presence of an intense laser field and by a static magnetic field are currently planned.« less

Authors:
Publication Date:
Research Org.:
Boston Univ., MA (USA)
OSTI Identifier:
5285374
Report Number(s):
DOE/ER/10444-1
TRN: 80-010858
DOE Contract Number:
AC02-79ER10444
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; GALLIUM ARSENIDES; ELECTRON DIFFRACTION; INDIUM ARSENIDES; INDIUM PHOSPHIDES; ABSORPTION SPECTRA; ELECTRIC CONDUCTIVITY; ENERGY TRANSFER; JUNCTION DIODES; LASER RADIATION; QUANTUM MECHANICS; ARSENIC COMPOUNDS; ARSENIDES; COHERENT SCATTERING; DIFFRACTION; ELECTRICAL PROPERTIES; ELECTROMAGNETIC RADIATION; GALLIUM COMPOUNDS; INDIUM COMPOUNDS; MECHANICS; PHOSPHIDES; PHOSPHORUS COMPOUNDS; PHYSICAL PROPERTIES; PNICTIDES; RADIATIONS; SCATTERING; SEMICONDUCTOR DEVICES; SEMICONDUCTOR DIODES; SPECTRA; 640301* - Atomic, Molecular & Chemical Physics- Beams & their Reactions; 656000 - Condensed Matter Physics

Citation Formats

Jensen, B. Infrared absorption spectrum of free carriers in polar semiconductors. Progress report, July 1, 1979-June 30, 1980. United States: N. p., 1980. Web. doi:10.2172/5285374.
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Jensen, B. Infrared absorption spectrum of free carriers in polar semiconductors. Progress report, July 1, 1979-June 30, 1980. United States. doi:10.2172/5285374.
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Jensen, B. Fri . "Infrared absorption spectrum of free carriers in polar semiconductors. Progress report, July 1, 1979-June 30, 1980". United States. doi:10.2172/5285374. https://www.osti.gov/servlets/purl/5285374.
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@article{osti_5285374,
title = {Infrared absorption spectrum of free carriers in polar semiconductors. Progress report, July 1, 1979-June 30, 1980},
author = {Jensen, B.},
abstractNote = {The Drude Zener theory of the absorption of high frequency radiation by free carriers (inverse bremsstrahlung) has been extended into the quantum region (h-bar omega > k/sub 0/T) in terms of a frequency dependent relaxation time which predicts the dc mobility in the quasiclassical limit. Numerical calculations of the frequency and concentration dependent electron scattering rate have been completed for InP, InAs, Ga/sub 0/ /sub 47/In/sub 0/ /sub 53/As, and previous results for GaAs extended to high carrier concentrations. When starting from a quantum statistical theory, the fact that n/sub q/oh-bar omega ..-->.. k/sub 0/T at low frequencies can be used to prevent the divergence of the coulomb scattering rate without inclusion of a screening radius. A result containing no adjustable parameters is found which predicts a mobility for uncompensated samples that decreases strongly at high concentrations. This has been observed in GaAs, and is not accounted for by the usual dc calculation which assumes h-bar omega = 0 and a screening parameter. Calculated results for GaAs are in good agreement with experimental measurements of the mobility which are found to be independent of a wide variety of conditions of material preparation. This indicates that disagreement with previous theoretical calculations was not due to compensation. Calculations for ZnSe and further investigation of the modification of the optical constants by the presence of an intense laser field and by a static magnetic field are currently planned.},
doi = {10.2172/5285374},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Fri Feb 01 00:00:00 EST 1980},
month = {Fri Feb 01 00:00:00 EST 1980}
}
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Technical Report:
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DOI:  10.2172/5285374
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