Ultrafast Enhancement of Ferromagnetism via Photoexcited Holes inGaMnAs

doi:10.1103/PhysRevLett.98.217401

Title: Ultrafast Enhancement of Ferromagnetism via Photoexcited Holes inGaMnAs

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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:: Wang, J.; Cotoros, I.; Dani, K.M.; Liu, X.; Furdyna, J.K.; Chemla, D.S.

Publication Date:: Sat Feb 17 00:00:00 EST 2007

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.

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                    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.

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                    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.

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@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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DOI: 10.1103/PhysRevLett.98.217401

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