We report ultrafast transient-grating measurements, above and below the Curie temperature, of the dilute ferromagnetic semiconductor (Ga,Mn)As containing 6% Mn. At 80 K (15 K), we observe that photoexcited electrons in the conduction band have a lifetime of 8 ps (5 ps) and diffuse at about 70 cm2/s (60 cm2/s). Such rapid diffusion requires either an electronic mobility exceeding 7,700 cm2/Vs or a conduction-band effective mass less than half the GaAs value. Our data suggest that neither the scattering rate nor the effective mass of the (Ga,Mn)As conduction band differs significantly from that of GaAs.
@article{arxiv.1303.0258,
title = {Rapid diffusion of electrons in GaMnAs},
author = {C. P. Weber and Eric A. Kittlaus and Kassandra B. Mattia and Christopher J. Waight and J. Hagmann and X. Liu and M. Dobrowolska and J. K. Furdyna},
journal= {arXiv preprint arXiv:1303.0258},
year = {2013}
}
Comments
5 pages, 3 figures. Differs from the previous version in incorporating additional data and changes made during the review process. Differs from the published version in including section headings and in omitting AIP copy-edits. No substantial differences in scientific conclusions from either version