Anomalous Hall Effect in IV-VI semimagnetic semiconductors
|Beata B. Brodowska 2, Witold Dobrowolski 2, Monika Arciszewska 2, Evgen I. Slynko 1, Vitalii Dugaev 1,3|
1. NAS of Ukraine, Institute for Problems of Material Science, Chernitsi Department, 5 I.Vilde str., Chernivtsi 58001, Ukraine
There is a growing interest in the Anomalous Hall Effect (AHE) due to the importance of the spin polarization and spin-orbit interaction for transport properties of materials and structures of spin electronics. In ferromagnetic metals and in magnetic semiconductors where the AHE can be observed, the transverse resistivity ρH contains a contribution proportional to magnetization M in addition to the usual Hall effect: ρH=R0B+μ0RSM, where B is the magnetic field, R0 and RS, respectively, are the normal and anomalous Hall coefficient, and μ0 is the magnetic constant. The purpose of our work is to study the AHE in IV-VI narrow gap ferromagnetic semiconductors: Sn1-xMnxTe, Sn1-x-yMnxEryTe, Sn1-xMnxEuyTe. The IV-VI systems were chosen for several reasons. These materials crystallize in the simple NaCl structure. Their energetic structure parameters are well known. The Curie temperatures are in the range 10-25 K what allows to perform measurements in a wide temperature range below and under the Curie temperature.
The samples used in our experiments were grown by the modified Bridgman method, their chemical composition was measured by microprobe technique and by X-ray dispersive fluorescence analysis. The Sn1-xMnxTe samples had 7.5% and 12% of manganese, Sn1-x-yMnxEryTe had 5.8% and 6% of manganese, and about 0.05% of erbium,the Sn1-x-yMnxEuyTe sample had 12.8% of manganese and 1.4% of europium. The Hall effect and electric conductivity measurements (up to 13 T in the temperature range 1.5-60 K) were performed using the standard DC technique. Magnetic properties were studied using Lake Shore 7229 Magnetometer/Susceptometer. Magnetization of those samples was measured at magnetic fields up to 9 T for the same temperatures as the /chi(T) dependence. As the result of the studies, both R0 and RS were evaluated and their dependence on temperature estimated.
Presentation: poster at E-MRS Fall Meeting 2005, Symposium D, by Beata B. Brodowska
See On-line Journal of E-MRS Fall Meeting 2005
Submitted: 2005-05-16 10:11 Revised: 2009-06-07 00:44