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Hanbury Brown Twiss effects in channel mixing normal-superconducting systems

M. Buttiker·P. Samuelsson
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Abstract

An investigation of the role of the proximity effect in current cross correlations in multiterminal, channel-mixing, normal-superconducting systems is presented. The proposed experiment is an electrical analog of the optical Hanbury Brown Twiss intensity cross correlation experiment. A chaotic quantum dot is connected via quantum point contacts to two normal and one superconducting reservoir. For dominating coupling of the dot to the superconducting reservoir, a magnetic flux of the order of a flux quantum in the dot suppresses the proximity effect and reverses the sign of the cross correlations, from positive to negative. In the opposite limit, for a dominating coupling to the normal reservoirs, the proximity effect is weak and the cross correlation are positive for a nonideal contact between the dot and the superconducting reservoir. We show that in this limit the correlations can be explained with particle counting arguments.

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M. Buttiker, P. Samuelsson. 2002-10-02. Hanbury Brown Twiss effects in channel mixing normal-superconducting systems. https://doi.org/10.1016/s1386-9477(02)00961-x

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