Author:
Wang M.,Howells B.,Marshall R. A.,Taylor J. M.,Edmonds K. W.,Rushforth A. W.,Campion R. P.,Gallagher B. L.
Abstract
AbstractWe present detailed experimental measurements and simulations of the field-dependent magnetization and magnetoresistance in the vicinity of the Curie temperature in the highly disordered dilute ferromagnetic semiconductor (Ga,Mn)As. The observed dependence of the magnetization on external magnetic field and temperature is consistent with three-dimensional Heisenberg equation of state calculations including a narrow distribution of critical temperatures. The magnetoresistance shows a peak at the Curie temperature due to the suppression of magnetic scattering in an applied magnetic field, which is well-described by considering changes in the square of the magnetization induced by the magnetic field.
Funder
FP7 Ideas: European Research Council
FP7 Nanosciences, Nanotechnologies, Materials and new Production Technologies
Engineering and Physical Sciences Research Council
Publisher
Springer Science and Business Media LLC
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