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Title: Influence of interband transitions on electron-phonon coupling measurements in Ni films

Abstract

The reduction in size and the increase in speed of opto- and magnetoelectronic devices is making the probability of nonequilibrium electron-phonon phenomena greater, leading to increased thermal resistance in these devices. The measurement of electron-phonon coupling in materials in these devices is becoming increasingly important for accurate thermal management. Here femtosecond thermoreflectance is used to measure the electron-phonon coupling factor in thin Ni films of varying thickness grown on Si and glass substrates. The thermoreflectance response is measured at 1.3 and 1.55 eV, yielding drastically different responses due to the Fermi-level transition at 1.3 eV in Ni. The influence of this transition on the thermoreflectance response results in a measurement of the electron-phonon coupling factor that is twice as high as that recorded in previous measurements that were unaffected by the Fermi-level transition.

Authors:
Publication Date:
Research Org.:
Thomas Jefferson National Accelerator Facility, Newport News, VA (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
1013011
Report Number(s):
JLAB-FEL-07-723; DOE/OR/23177-1545
Journal ID: AOPOAI; TRN: US201110%%341
DOE Contract Number:
AC05-06OR23177
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Optics; Journal Volume: 46; Journal Issue: 11
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ELECTRON-PHONON COUPLING; NICKEL; FILMS; FERMI LEVEL; PROBABILITY; SUBSTRATES; THICKNESS; TEMPERATURE CONTROL

Citation Formats

Patrick E. Hopkins, J. Michael Klopf, Pamela M. Norris. Influence of interband transitions on electron-phonon coupling measurements in Ni films. United States: N. p., 2007. Web. doi:10.1364/AO.46.002076.
Patrick E. Hopkins, J. Michael Klopf, Pamela M. Norris. Influence of interband transitions on electron-phonon coupling measurements in Ni films. United States. doi:10.1364/AO.46.002076.
Patrick E. Hopkins, J. Michael Klopf, Pamela M. Norris. Thu . "Influence of interband transitions on electron-phonon coupling measurements in Ni films". United States. doi:10.1364/AO.46.002076.
@article{osti_1013011,
title = {Influence of interband transitions on electron-phonon coupling measurements in Ni films},
author = {Patrick E. Hopkins, J. Michael Klopf, Pamela M. Norris},
abstractNote = {The reduction in size and the increase in speed of opto- and magnetoelectronic devices is making the probability of nonequilibrium electron-phonon phenomena greater, leading to increased thermal resistance in these devices. The measurement of electron-phonon coupling in materials in these devices is becoming increasingly important for accurate thermal management. Here femtosecond thermoreflectance is used to measure the electron-phonon coupling factor in thin Ni films of varying thickness grown on Si and glass substrates. The thermoreflectance response is measured at 1.3 and 1.55 eV, yielding drastically different responses due to the Fermi-level transition at 1.3 eV in Ni. The influence of this transition on the thermoreflectance response results in a measurement of the electron-phonon coupling factor that is twice as high as that recorded in previous measurements that were unaffected by the Fermi-level transition.},
doi = {10.1364/AO.46.002076},
journal = {Applied Optics},
number = 11,
volume = 46,
place = {United States},
year = {Thu Mar 01 00:00:00 EST 2007},
month = {Thu Mar 01 00:00:00 EST 2007}
}
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