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Commensurability effects in Andreev antidot billiards

J. Eroms·M. Tolkiehn·D. Weiss·U. Rössler·J. De Boeck·G. Borghs
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Abstract

An Andreev billiard was realized in an array of niobium filled antidots in a high-mobility InAs/AlGaSb heterostructure. Below the critical temperature T_C of the Nb dots we observe a strong reduction of the resistance around B=0 and a suppression of the commensurability peaks, which are usually found in antidot lattices. Both effects can be explained in a classical Kubo approach by considering the trajectories of charge carriers in the semiconductor, when Andreev reflection at the semiconductor-superconductor interface is included. For perfect Andreev reflection, we expect a complete suppression of the commensurability features, even though motion at finite B is chaotic.

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J. Eroms, M. Tolkiehn, D. Weiss, U. Rössler, J. De Boeck, G. Borghs. 2001-07-09. Commensurability effects in Andreev antidot billiards. https://doi.org/10.1209/epl%2Fi2002-00433-3

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