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Anomalous Hall effect in insulating Ga1-xMnxAs

Sh. U. Yuldashev·H. C. Jeon·H. S. Im·T. W. Kang·S. H. Lee·J. K. Furdyna
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Abstract

We have investigated the effect of doping by Te on the anomalous Hall effect in Ga1-xMnxAs (x = 0.085). For this relatively high value of x the temperature dependence of resistivity shows an insulating behavior. It is well known that in Ga1-xMnxAs the Mn ions naturally act as acceptors. Additional doping by Te donors decreases the Curie temperature and increases the anomalous Hall resistivity. With increasing Te concentration the long-range ferromagnetic order in Ga1-xMnxAs eventually disappears, and paramagnetic-to-spin glass transition is observed instead. The critical concentration of holes required for establishing ferromagnetic order in Ga1-xMnxAs (x = 0.085) has been estimated by using the magnetic polaron percolation theory proposed by Kaminski and Das Sarma [Phys.Rev.Lett. 88, 247202 (2002)].

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Sh. U. Yuldashev, H. C. Jeon, H. S. Im, T. W. Kang, S. H. Lee, J. K. Furdyna. 2004-08-20. Anomalous Hall effect in insulating Ga1-xMnxAs. https://doi.org/10.1103/physrevb.70.193203

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