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arXiv · 1504.06208

Tunneling spectroscopy and Josephson current of superconductor-ferromagnet hybrids on the surface of a 3D TI

Bo Lu·Pablo Burset·Keiji Yada·Yukio Tanaka
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Abstract

We investigate the charge transport property of superconductor (S) /normal metal (N) / ferromagnet insulator (FI) /(normal metal) N' and S/N/FI/N'/S Josephson junctions on a three-dimensional topological insulator surface. We find asymmetric local density of states (LDOSs) in a S/N/FI/N' junction and show that the finite length of the N interlayer gives rise to subgap resonant spikes in the differential conductance and LDOSs. In a S/N/FI/N'/S junction, the Josephson current shows a non-sinusoidal current-phase relation and the N (or N') interlayer decreases the magnitude of the critical current monotonically.

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Bo Lu, Pablo Burset, Keiji Yada, Yukio Tanaka. 2015-06-04. Tunneling spectroscopy and Josephson current of superconductor-ferromagnet hybrids on the surface of a 3D TI. https://doi.org/10.1088/0953-2048%2F28%2F10%2F105001

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