Proximity effects in a superconductor-normal metal bilayer system

Naushad Ahmad Kamar; N. S. Vidhyadhiraja

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arXiv · 1403.1972

Proximity effects in a superconductor-normal metal bilayer system

Naushad Ahmad Kamar·N. S. Vidhyadhiraja

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Abstract

In this letter, we have studied the effects of proximity of a superconductor to a normal metal. The system, represented by a bilayer attractive Hubbard model, is investigated using layer-dynamical mean field theory and iterated perturbation theory for superconductivity as an impurity solver. The bilayer system comprises a superconducting and a normal metallic layer, connected by an inter-planar hopping ($t_\perp$). It is found that superconductivity is induced in the normal layer for small $t_\perp$. With increasing inter-layer hopping, the bilayer system undergoes two transitions: a first order transition to a normal metallic phase, and subsequently a continuous crossover to a band insulator.

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Naushad Ahmad Kamar, N. S. Vidhyadhiraja. 2014-03-08. Proximity effects in a superconductor-normal metal bilayer system. https://arxiv.org/abs/1403.1972

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