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arXiv · 0711.0534

Hysteretic magnetotransport in p-type AlGaAs heterostructures with In/Zn/Au ohmic contacts

B. Grbic·R. Leturcq·T. Ihn·K. Ensslin·G. Blatter·D. Reuter·A. D. Wieck
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Abstract

The two-terminal magneto-conductance of a hole gas in C-doped AlGaAs/GaAs heterostructures with ohmic contacts consisting of alloyed In/Zn/Au displays a pronounced hysteresis of the conductance around zero magnetic field. The hysteresis disappears above magnetic fields of around 0.5 T and temperatures above 300 mK. For magnetic fields below 10 mT we observe a pronounced dip in the magneto-conductance. We tentatively discuss these experimental observations in the light of superconductivity of the ohmic contacts.

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B. Grbic, R. Leturcq, T. Ihn, K. Ensslin, G. Blatter, D. Reuter, A. D. Wieck. 2007-11-05. Hysteretic magnetotransport in p-type AlGaAs heterostructures with In/Zn/Au ohmic contacts. https://doi.org/10.1103/physrevb.77.245307

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