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Four-point measurements of n- and p-type two-dimensional systems fabricated with cleaved-edge overgrowth

M. Grayson·S. F. Roth·Y. Xiang·F. Fischer·D. Schuh·M. Bichler
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Abstract

We demonstrate a contact design that allows four-terminal magnetotransport measurements of cleaved-edge overgrown two-dimensional electron and hole systems. By lithographically patterning and etching a bulk-doped surface layer, finger-shaped leads are fabricated, which contact the two-dimensional systems on the cleave facet. Both n- and p-type two-dimensional systems are demonstrated at the cleaved edge, using Si as either donor or acceptor, dependent on the growth conditions. Four-point measurements of both gated and modulation-doped samples yield fractional quantum Hall features for both n- and p-type, with several higher-order fractions evident in n-type modulation-doped samples.

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M. Grayson, S. F. Roth, Y. Xiang, F. Fischer, D. Schuh, M. Bichler. 2005-11-02. Four-point measurements of n- and p-type two-dimensional systems fabricated with cleaved-edge overgrowth. https://doi.org/10.1063/1.2135407

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