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arXiv · 0912.4716

Theory of non-Abelian Fabry-Perot interferometry in topological insulators

Johan Nilsson·A. R. Akhmerov
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Abstract

Interferometry of non-Abelian edge excitations is a useful tool in topological quantum computing. In this paper we present a theory of a non-Abelian edge state interferometer in a 3D topological insulator brought in proximity to an s-wave superconductor. The non-Abelian edge excitations in this system have the same statistics as in the previously studied 5/2 fractional quantum Hall (FQH) effect and chiral p-wave superconductors. There are however crucial differences between the setup we consider and these systems, like the need for a converter between charged and neutral excitations and the neutrality of the non-Abelian excitations. These differences manifest themselves in a temperature scaling exponent of -7/4 for the conductance instead of -3/2 as in the 5/2 FQH effect.

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Johan Nilsson, A. R. Akhmerov. 2009-12-23. Theory of non-Abelian Fabry-Perot interferometry in topological insulators. https://doi.org/10.1103/physrevb.81.205110

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