Study on Green's function on TI surface

Bo Lu; Yukio Tanaka

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arXiv · 1512.00916

Study on Green's function on TI surface

Bo Lu·Yukio Tanaka

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Abstract

In theory of superconducting junctions, Green's function has an important role to obtain Andreev bound states, local density of states and Josephson current in a systematic way. In this article, we show how to construct Green's function on the surface of topological insulator following McMillan's formalism where the energy spectrum of electrons obeys a linear dispersion. For a model of superconductor (S)/ferromagnet (F)/normal metal (N) junction, we show that the generation of Majorana Fermion gives rise to the enhanced local density of states and pair amplitude of odd-frequency pairing. We also derive an extended Furusaki-Tsukada's formula of d.c. Josephson current in S/F/S junctions. The obtained Josephson current depends on the direction and magnitude of the magnetization.

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Bo Lu, Yukio Tanaka. 2016-01-26. Study on Green's function on TI surface. https://arxiv.org/abs/1512.00916

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