Authors:	Demsar, Jure
Title:	Non-equilibrium phenomena in superconductors probed by femtosecond time-domain spectroscopy
Online publication date:	1-Jun-2021
Year of first publication:	2020
Language:	english
Abstract:	Development of ultrafast lasers and nonlinear optical techniques over the last two decades provides tools to access real-time dynamics of low energy excitations in superconductors. For example, time-resolved THz spectroscopy and time- and angular-resolved photoemission spectroscopy provide access to the real-time dynamics of the superconducting gap amplitude. Such studies enable determination of microscopic parameters like quasi-particle recombination rates, pair-breaking rates and electron–boson coupling constants. Recently, intense THz pulses have been used to probe the nonlinear dynamics, including observation of collective modes. Moreover, using low-frequency electromagnetic pulses, there are several reports of amplification of superconductivity in both conventional and unconventional superconductors. Starting with a brief historical overview of the pioneering work, where non-equilibrium phenomena in superconductors were investigated using quasi-continuous excitation, we review some of the insights that are provided by using real-time approaches. We focus on conventional BCS superconductors, whose ground state is reasonably well understood, and address similarities and open questions related to the corresponding studies in high-𝑇𝑐 T c superconductors.
DDC:	530 Physik 530 Physics
Institution:	Johannes Gutenberg-Universität Mainz
Department:	FB 08 Physik, Mathematik u. Informatik
Place:	Mainz
ROR:	https://ror.org/023b0x485
DOI:	http://doi.org/10.25358/openscience-5965
Version:	Published version
Publication type:	Zeitschriftenaufsatz
License:	CC BY
Information on rights of use:	https://creativecommons.org/licenses/by/4.0/
Journal:	Journal of low temperature physics 201
Pages or article number:	676 709
Publisher:	Springer Science + Business Media B.V.
Publisher place:	Dordrecht
Issue date:	2020
ISSN:	1573-7357
Publisher URL:	https://doi.org/10.1007/s10909-020-02461-y
Publisher DOI:	10.1007/s10909-020-02461-y
Appears in collections:	JGU-Publikationen