English

Magnetic Interactions in Ge/1-x/Cr/x/Te Semimagnetic Semiconductors

Materials Science 2012-12-24 v2

Abstract

We present the studies of magnetic properties of Ge/1-x/Cr/x/Te diluted magnetic semiconductor with changeable chemical composition 0.016 \leq x \leq 0.061. A spin-glass state (at T \leq 35 K) for x = 0.016 and 0.025 and a ferromagnetic phase (at T < 60 K) for x \geq 0.030 are observed. The long range carrier-mediated magnetic interactions are found to be responsible for the observed magnetic ordering for x < 0.045, while for x \geq 0.045 the spinodal decomposition of Cr ions leads to a maximum and decrease of the Curie temperature, TC, with increasing x. The calculations based on spin waves model are able to reproduce the observed magnetic properties at a homogeneous limit of Cr alloying, e.g. x < 0.04, and prove that carrier mediated Ruderman-Kittel-Kasuya-Yosida (RKKY) interaction is responsible for the observed magnetic states. The value of the Cr-hole exchange integral, Jpd, estimated via fitting of the experimental results with the theoretical model, is in the limits 0.77...0.88 eV.

Keywords

Cite

@article{arxiv.1203.3044,
  title  = {Magnetic Interactions in Ge/1-x/Cr/x/Te Semimagnetic Semiconductors},
  author = {L. Kilanski and A. Podgórni and W. Dobrowolski and M. Górska and B. J. Kowalski and A. Reszka and V. Domukhovski and A. Szczerbakow and K. Szałowski and J. R. Anderson and N. P. Butch and V. E. Slynko and E. I. Slynko},
  journal= {arXiv preprint arXiv:1203.3044},
  year   = {2012}
}

Comments

8 pages, 7 figures