Stabilization of magnetic polarons in antiferromagnetic semiconductors by extended spin distortions

Article

Abstract.

We study the problem of a magnetic polaron in an one-dimensional antiferromagnetic semiconductor (ferron). We obtain an analytical solution for the distortion produced in the antiferromagnetic structure due to the presence of a charge carrier bound to an impurity. The region in which the charge carrier is trapped is of the order of the lattice constant (small ferron) but the distortion of the magnetic structure extends over a much larger distance. It is shown that the presence of this distortion makes the ferron more stable, and introduces a new length scale in the problem.

Keywords

Charge Carrier Large Distance Magnetic Structure Ferron Magnetic Polaron 

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Copyright information

© Springer-Verlag Berlin/Heidelberg 2004

Authors and Affiliations

  1. 1.Departamento de Física AplicadaUniversidade de Santiago de CompostelaSantiago de CompostelaSpain

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