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arXiv · 1004.0750

Quantum impurity spin in Majorana edge fermions

Ryuichi Shindou·Akira Furusaki·Naoto Nagaosa
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Abstract

We show that Majorana edge modes of two-dimensional spin-triplet topological superconductors have Ising-like spin density whose direction is determined by the d-vector characterizing the spin-triplet pairing symmetry. Exchange coupling between an impurity spin (S=1/2) and Majorana edge modes is thus Ising-type. Under external magnetic field perpendicular to the Ising axis, the system can be mapped to a two-level system with Ohmic dissipation, which is equivalent to the anisotropic Kondo model. The magnetic response of the impurity spin can serve as a local experimental probe for the order parameter.

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Ryuichi Shindou, Akira Furusaki, Naoto Nagaosa. 2010-11-04. Quantum impurity spin in Majorana edge fermions. https://doi.org/10.1103/physrevb.82.180505

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