Journal of Superconductivity

, Volume 18, Issue 3, pp 315–320

Magnetic Interactions in Granular Paramagnetic–Ferromagnetic GaAs: Mn/MnAs Hybrids

  • W. Heimbrodt
  • P. J. Klar
  • S. Ye
  • M. Lampalzer
  • C. Michel
  • S. D. Baranovskii
  • P. Thomas
  • W. Stolz
Original Article

DOI: 10.1007/s10948-005-0001-6

Cite this article as:
Heimbrodt, W., Klar, P.J., Ye, S. et al. J Supercond (2005) 18: 315. doi:10.1007/s10948-005-0001-6

Abstract

The magneto-transport properties of granular paramagnetic–ferromagnetic GaAs:Mn/MnAs hybrids have been studied. Positive and negative magnetoresistivity can be observed in the paramagnetic matrix as well as in the GaAs:Mn/MnAs hybrid system. The experimental results and the respective relevant interactions are discussed. A phenomenological explanation from a microscopic point of view is presented. It is suggested that the paramagnetism of the matrix plays a major role in the magneto-resistive behavior of the hybrids, in contrast to diamagnetic–ferromagnetic hybrids where the magnetoresistance (MR) is dominated by the ferromagnetism of the clusters.

KEY WORDS:

paramagnetic–ferromagnetic hybrids GaMnAs/MnAs magneto-transport 

Copyright information

© Springer Science+Business Media, Inc. 2005

Authors and Affiliations

  • W. Heimbrodt
    • 1
  • P. J. Klar
    • 1
  • S. Ye
    • 1
  • M. Lampalzer
    • 1
  • C. Michel
    • 1
  • S. D. Baranovskii
    • 1
  • P. Thomas
    • 1
  • W. Stolz
    • 1
  1. 1.Department of Physics and Material Sciences CenterPhilipps-University of MarburgMarburgGermany