Direct Observation of the Spin Exciton in Andreev Spectroscopy of Iron-Based Superconductors

Overview

Journal Materials (Basel)

Publisher MDPI

Date 2022 Sep 9

PMID 36079499

Authors

Maxim M Korshunov

Svetoslav A Kuzmichev

Tatiana E Kuzmicheva

Affiliations

Soon will be listed here.

Abstract

Quasiparticle excitations provide viable information on the physics of unconventional superconductors. Higgs and Leggett modes are some of the classic examples. Another important bosonic excitation is the spin exciton originating from the sign-changing superconducting gap structure. Here we report a direct observation of the temperature-dependent spin exciton in the Andreev spectra of iron-based superconductors. Combined with the other experimental evidence, our observation confirms the extended -wave (s±) order parameter symmetry and indirectly proves the spin-fluctuation mechanism of Cooper pairing.

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