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Title: High-resolution spectroscopy of the zero-phonon line of the deep donor EL2 in GaAs

Abstract

We investigated the zero-phonon line (ZPL) of the deep donor EL2 in GaAs by means of high-resolution absorption spectroscopy with a narrow-band laser. Frequency-selective bleaching ({open_quotes}spectral-hole burning{close_quotes}) experiments and the measurement of the temperature broadening of the ZPL prove an essentially homogeneous broadening of the transition. The observed asymmetry of the line shape is interpreted to be caused by a Fano resonance of the {sup 1}T{sub 2} excited state with the conduction band. A splitting of the {sup 1}T{sub 2} state as the reason for the asymmetry seems unrealistic. The homogeneous broadening of the ZPL prevents the use of spectral-hole burning spectroscopy to study the effect of external perturbations on the ZPL of the EL2. {copyright} {ital 1997} {ital The American Physical Society}

Authors:
; ; ;  [1]
  1. Institut fuer Werkstoffwissenschaften VI, Universitaet Erlangen, Martensstrasse 7, D-91058 Erlangen (Germany)
Publication Date:
OSTI Identifier:
503713
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review, B: Condensed Matter; Journal Volume: 55; Journal Issue: 20; Other Information: PBD: May 1997
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; GALLIUM ARSENIDES; ABSORPTION SPECTROSCOPY; LINE BROADENING; ENERGY-LEVEL TRANSITIONS; FANO FACTOR; CRYSTAL DEFECTS; INFRARED SPECTRA

Citation Formats

Hecht, C., Kummer, R., Thoms, M., and Winnacker, A. High-resolution spectroscopy of the zero-phonon line of the deep donor EL2 in GaAs. United States: N. p., 1997. Web. doi:10.1103/PhysRevB.55.13625.
Hecht, C., Kummer, R., Thoms, M., & Winnacker, A. High-resolution spectroscopy of the zero-phonon line of the deep donor EL2 in GaAs. United States. doi:10.1103/PhysRevB.55.13625.
Hecht, C., Kummer, R., Thoms, M., and Winnacker, A. 1997. "High-resolution spectroscopy of the zero-phonon line of the deep donor EL2 in GaAs". United States. doi:10.1103/PhysRevB.55.13625.
@article{osti_503713,
title = {High-resolution spectroscopy of the zero-phonon line of the deep donor EL2 in GaAs},
author = {Hecht, C. and Kummer, R. and Thoms, M. and Winnacker, A.},
abstractNote = {We investigated the zero-phonon line (ZPL) of the deep donor EL2 in GaAs by means of high-resolution absorption spectroscopy with a narrow-band laser. Frequency-selective bleaching ({open_quotes}spectral-hole burning{close_quotes}) experiments and the measurement of the temperature broadening of the ZPL prove an essentially homogeneous broadening of the transition. The observed asymmetry of the line shape is interpreted to be caused by a Fano resonance of the {sup 1}T{sub 2} excited state with the conduction band. A splitting of the {sup 1}T{sub 2} state as the reason for the asymmetry seems unrealistic. The homogeneous broadening of the ZPL prevents the use of spectral-hole burning spectroscopy to study the effect of external perturbations on the ZPL of the EL2. {copyright} {ital 1997} {ital The American Physical Society}},
doi = {10.1103/PhysRevB.55.13625},
journal = {Physical Review, B: Condensed Matter},
number = 20,
volume = 55,
place = {United States},
year = 1997,
month = 5
}
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