Proximity effect in a heterostructure of a high $T_c$ superconductor with a topological insulator from Dynamical mean field theory

Xiancong Lu; David Sénéchal

doi:10.1103/physrevb.101.054512

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arXiv · 1911.11898

Proximity effect in a heterostructure of a high $T_c$ superconductor with a topological insulator from Dynamical mean field theory

Xiancong Lu·David Sénéchal

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Abstract

We investigate the proximity effect in a heterostructure of the topological insulator (TI) \BiSe\ deposited on the HTSC material BSCCO. The latter is described by the one-band Hubbard model and is treated with cluster dynamical mean field theory (CDMFT), the TI layers being included via the CDMFT self-consistency loop. The penetration of superconductivity into the TI depends on the position of the Fermi level with respect to the TI gap. We illustrate the back action of the TI layer on the HTSC layer, in particular the gradual disappearance of Mott physics with increasing tunneling amplitude.

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Xiancong Lu, David Sénéchal. 2019-11-27. Proximity effect in a heterostructure of a high $T_c$ superconductor with a topological insulator from Dynamical mean field theory. https://doi.org/10.1103/physrevb.101.054512

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