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arXiv · 1607.06100

Conformal energy currents on the edge of a topological superconductor

Chris N. Self·Jiannis K. Pachos·James R. Wootton·Sofyan Iblisdir
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Abstract

The boundary of a 2D topological superconductor can be modeled by a conformal field theory. Here we demonstrate the behaviors of this high level description emerging from a microscopic model at finite temperatures. To achieve that, we analyze the low energy sector of Kitaev's honeycomb lattice model and probe its energy current. We observe that the scaling of the energy current with temperature reveals the central charge of the conformal field theory, which is in agreement with the Chern number of the bulk. Importantly, these currents can discriminate between distinct topological phases at finite temperatures. We assess the resilience of this measurement of the central charge under coupling disorder, bulk dimerisation and defects at the boundary, thus establishing it as a favorable means of experimentally probing topological superconductors.

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Chris N. Self, Jiannis K. Pachos, James R. Wootton, Sofyan Iblisdir. 2017-02-23. Conformal energy currents on the edge of a topological superconductor. https://doi.org/10.1103/physrevb.95.115141

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