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arXiv · 1509.03166

Chiral nodes and oscillations in the Josephson current in Weyl semimetals

Udit Khanna·Dibya Kanti Mukherjee·Arijit Kundu·Sumathi Rao
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Abstract

The separation of the Weyl nodes in a broken time-reversal symmetric Weyl semimetal leads to helical quasi-particle excitations at the Weyl nodes, which, when coupled with overall spin conservation allows only inter-nodal transport at the junction of the Weyl semimetal with a superconductor. This leads to an unusual periodic oscillation in the Josephson current as a function of $k_0L$, where $L$ is the length of the Weyl semimetal and $2k_0$ is the inter-nodal distance. This oscillation is robust and should be experimentally measurable, providing a direct path to confirming the existence of chiral nodes in the Weyl semimetal.

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Udit Khanna, Dibya Kanti Mukherjee, Arijit Kundu, Sumathi Rao. 2015-09-10. Chiral nodes and oscillations in the Josephson current in Weyl semimetals. https://doi.org/10.1103/physrevb.93.121409

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