Diluted Magnetic Semiconductors in High Magnetic Fields

• Authors: Y. Shapira
• Languages of publication: EN

Abstracts

EN

Magnetization studies of diluted magnetic semiconductors in high fields are reviewed. Magnetization steps due to pairs were originally used to mea­sure the near neighbor exchange constant J_{1}. They are now also used to determine: (1) the smaller exchange constants J_{2} and J_{3}, (2) the differ­ence between J_{1}'s for inequivalent near neighbors in wurtzite diluted mag­netic semiconductors, and (3) the Dzyaloshinski-Moriya interaction. A dif­ferent type of magnetization step, due to isolated ions, is used to deter­mine the uniaxial anisotropy of Co^{++} ions in wurtzite diluted magnetic semiconductors. In Fe-based diluted magnetic semiconductors the high-field magnetization exhibits two effects: (1) strong dependence on field direction in cubic diluted magnetic semiconductors, and (2) reversal of the uniax­ial magnetization-anisotropy in wurtzite diluted magnetic semiconductors. In (100) EuTe/PbTe superlattices the antiferromagnetic transition, both at zero and finite H, is depressed when the EuTe layer becomes only a few monolayers thick. The easy directions are in the (100) plane of the layer, which is explained by the dipole-dipole anisotropy.

Keywords

EN

75.70.Fr; 75.50.Pp; 75.30.Et

• Journal: Acta Physica Polonica A
• Year: 1995
• Volume: 87
• Issue: 1
• Pages: 107-117

Dates

published

1995-01

Contributors

author

Y. Shapira

• Department of Physics, Tufts University, Medford MA 02155, USA