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Proposal to stabilize and detect half-quantum vortices in strontium ruthenate thin films: Non-Abelian braiding statistics of vortex matter in a ${p_x}+i{p_y}$ superconductor

Sankar Das Sarma·Chetan Nayak·Sumanta Tewari
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Abstract

We propose a simple way to stabilize half-quantum vortices in superconducting strontium ruthenate, assuming the order parameter is of chiral $p_x + ip_y$ symmetry, as is suggested by recent experiments. The method, first given by Salomaa and Volovik in the context of Helium-3, is very naturally suited for strontium ruthenate, which has a layered, quasi-two-dimensional, perovskite crystal structure. We propose possible experiments to detect their non abelian-braiding statistics. These experiments are of potential importance for topological quantum computation.

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Sankar Das Sarma, Chetan Nayak, Sumanta Tewari. 2005-10-26. Proposal to stabilize and detect half-quantum vortices in strontium ruthenate thin films: Non-Abelian braiding statistics of vortex matter in a ${p_x}+i{p_y}$ superconductor. https://doi.org/10.1103/physrevb.73.220502

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