Coherent Coupling Between Vortex Bound States and Magnetic Impurities in 2D Layered Superconductors

Overview

Journal Nat Commun

Specialty Biology

Date 2021 Aug 4

PMID 34344878

Authors

Sunghun Park

Victor Barrena

Samuel Manas-Valero

Jose J Baldovi

Anton Fente

Edwin Herrera

Federico Mompean

Mar Garcia-Hernandez

Angel Rubio

Eugenio Coronado

Isabel Guillamon

Alfredo Levy Yeyati

Hermann Suderow

Affiliations

Soon will be listed here.

Abstract

Bound states in superconductors are expected to exhibit a spatially resolved electron-hole asymmetry which is the hallmark of their quantum nature. This asymmetry manifests as oscillations at the Fermi wavelength, which is usually tiny and thus washed out by thermal broadening or by scattering at defects. Here we demonstrate theoretically and confirm experimentally that, when coupled to magnetic impurities, bound states in a vortex core exhibit an emergent axial electron-hole asymmetry on a much longer scale, set by the coherence length. We study vortices in 2H-NbSe and in 2H-NbSeS with magnetic impurities, characterizing these with detailed Hubbard-corrected density functional calculations. We find that the induced electron-hole imbalance depends on the band character of the superconducting material. Our results show that coupling between quantum bound states in superconductors is remarkably robust and has a strong influence in tunneling measurements.

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