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Anisotropic magnetoresistance of two-dimensional holes in GaAs
Papadakis1, De Poortere EP, Shayegan
1Department of Electrical Engineering, Princeton University, Princeton, New Jersey 08544, USA.
Abstract:
Experiments on high-quality GaAs (311)A two-dimensional holes at low temperatures reveal a remarkable dependence of the magnetoresistance, measured with an in-plane magnetic field ( B), on the direction of B relative to both the crystal axes and the current direction. The magnetoresistance features, and in particular the value of B above which the resistivity exhibits an insulating behavior, depend on the orientation of B. To explain the data, the anisotropic band structure of the holes and a repopulation of the spin subbands in the presence of B, as well as the coupling of the orbital motion to B, need to be taken into account.
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