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Title: Ultrafast Enhancement of Ferromagnetism via Photoexcited Holes inGaMnAs

Abstract

We report on the observation of ultrafast photo-enhanced ferromagnetism in GaMnAs. It is manifested as a transient magnetization increase on a 100-ps time scale, after an initial sub-ps demagnetization. The dynamic magnetization enhancement exhibits a maximum below the Curie temperature {Tc} and dominates the demagnetization component when approaching {Tc}. We attribute the observed ultrafast collective ordering to the p-d exchange interaction between photoexcited holes and Mn spins, leading to a correlation-induced peak around 20K and a transient increase in {Tc}.

Authors:
; ; ; ; ;
Publication Date:
Research Org.:
Ernest Orlando Lawrence Berkeley NationalLaboratory, Berkeley, CA (US)
Sponsoring Org.:
USDOE Director. Office of Science. Basic EnergySciences
OSTI Identifier:
918935
Report Number(s):
LBNL-62724
Journal ID: ISSN 0031-9007; PRLTAO; R&D Project: 504901; BnR: KC0202020; TRN: US200819%%512
DOE Contract Number:
DE-AC02-05CH11231
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 98; Journal Issue: 21; Related Information: Journal Publication Date: May 22, 2007
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; CURIE POINT; DEMAGNETIZATION; EXCHANGE INTERACTIONS; FERROMAGNETISM; MAGNETIZATION; TRANSIENTS

Citation Formats

Wang, J., Cotoros, I., Dani, K.M., Liu, X., Furdyna, J.K., and Chemla, D.S. Ultrafast Enhancement of Ferromagnetism via Photoexcited Holes inGaMnAs. United States: N. p., 2007. Web. doi:10.1103/PhysRevLett.98.217401.
Wang, J., Cotoros, I., Dani, K.M., Liu, X., Furdyna, J.K., & Chemla, D.S. Ultrafast Enhancement of Ferromagnetism via Photoexcited Holes inGaMnAs. United States. doi:10.1103/PhysRevLett.98.217401.
Wang, J., Cotoros, I., Dani, K.M., Liu, X., Furdyna, J.K., and Chemla, D.S. Sat . "Ultrafast Enhancement of Ferromagnetism via Photoexcited Holes inGaMnAs". United States. doi:10.1103/PhysRevLett.98.217401. https://www.osti.gov/servlets/purl/918935.
@article{osti_918935,
title = {Ultrafast Enhancement of Ferromagnetism via Photoexcited Holes inGaMnAs},
author = {Wang, J. and Cotoros, I. and Dani, K.M. and Liu, X. and Furdyna, J.K. and Chemla, D.S.},
abstractNote = {We report on the observation of ultrafast photo-enhanced ferromagnetism in GaMnAs. It is manifested as a transient magnetization increase on a 100-ps time scale, after an initial sub-ps demagnetization. The dynamic magnetization enhancement exhibits a maximum below the Curie temperature {Tc} and dominates the demagnetization component when approaching {Tc}. We attribute the observed ultrafast collective ordering to the p-d exchange interaction between photoexcited holes and Mn spins, leading to a correlation-induced peak around 20K and a transient increase in {Tc}.},
doi = {10.1103/PhysRevLett.98.217401},
journal = {Physical Review Letters},
number = 21,
volume = 98,
place = {United States},
year = {Sat Feb 17 00:00:00 EST 2007},
month = {Sat Feb 17 00:00:00 EST 2007}
}
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