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Title: Photoinduced Volume Change in Arsenic Chalcogenides by Band-Gap Light

Abstract

Photoinduced structural changes in molecular semicrystalline As4Se3 films have been characterized by extended x-ray absorption fine structure and x-ray diffraction under in situ band-gap laser illumination. Transient and permanent changes in the local and long-range structure have been determined quantitatively. In contrast to fully amorphous arsenic selenide films, a photoinduced contraction has been observed in semicrystalline As4Se3 films. A comprehensive phenomenological model is proposed for the photoinduced volume change in As-based chalcogenides. This model is based on two competing processes viz. intermolecular interaction through Coulombic repulsive force that results in photoexpansion, and cross-linking of molecular units through bond switching that causes photocontraction. A guideline is presented for selecting chalcogenide glass composition with specific photoinduced volume change characteristics.

Authors:
; ; ;
Publication Date:
Research Org.:
Brookhaven National Laboratory (BNL) National Synchrotron Light Source
Sponsoring Org.:
Doe - Office Of Science
OSTI Identifier:
930675
Report Number(s):
BNL-81190-2008-JA
TRN: US200901%%26
DOE Contract Number:
DE-AC02-98CH10886
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review B: Condensed Matter and Materials Physics; Journal Volume: 74
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ARSENIC SELENIDES; CHALCOGENIDES; MORPHOLOGICAL CHANGES; LASER RADIATION; MATHEMATICAL MODELS; national synchrotron light source

Citation Formats

Chen,G., Jain, H., Vlcek, M., and Ganjoo, A. Photoinduced Volume Change in Arsenic Chalcogenides by Band-Gap Light. United States: N. p., 2007. Web.
Chen,G., Jain, H., Vlcek, M., & Ganjoo, A. Photoinduced Volume Change in Arsenic Chalcogenides by Band-Gap Light. United States.
Chen,G., Jain, H., Vlcek, M., and Ganjoo, A. Mon . "Photoinduced Volume Change in Arsenic Chalcogenides by Band-Gap Light". United States. doi:.
@article{osti_930675,
title = {Photoinduced Volume Change in Arsenic Chalcogenides by Band-Gap Light},
author = {Chen,G. and Jain, H. and Vlcek, M. and Ganjoo, A.},
abstractNote = {Photoinduced structural changes in molecular semicrystalline As4Se3 films have been characterized by extended x-ray absorption fine structure and x-ray diffraction under in situ band-gap laser illumination. Transient and permanent changes in the local and long-range structure have been determined quantitatively. In contrast to fully amorphous arsenic selenide films, a photoinduced contraction has been observed in semicrystalline As4Se3 films. A comprehensive phenomenological model is proposed for the photoinduced volume change in As-based chalcogenides. This model is based on two competing processes viz. intermolecular interaction through Coulombic repulsive force that results in photoexpansion, and cross-linking of molecular units through bond switching that causes photocontraction. A guideline is presented for selecting chalcogenide glass composition with specific photoinduced volume change characteristics.},
doi = {},
journal = {Physical Review B: Condensed Matter and Materials Physics},
number = ,
volume = 74,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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