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Title: Theory of parametrically amplified electron-phonon superconductivity

Abstract

Ultrafast optical manipulation of ordered phases in strongly correlated materials is a topic of significant theoretical, experimental, and technological interest. Inspired by a recent experiment on light-induced superconductivity in fullerenes [M. Mitrano et al., Nature (London) 530, 461 (2016)], we develop a comprehensive theory of light-induced superconductivity in driven electron-phonon systemswith lattice nonlinearities. In analogy with the operation of parametric amplifiers, we show how the interplay between the external drive and lattice nonlinearities lead to significantly enhanced effective electron-phonon couplings. We provide a detailed and unbiased study of the nonequilibrium dynamics of the driven system using the real-time Green's function technique. To this end, we develop a Floquet generalization of the Migdal-Eliashberg theory and derive a numerically tractable set of quantum Floquet-Boltzmann kinetic equations for the coupled electron-phonon system. We study the role of parametric phonon generation and electronic heating in destroying the transient superconducting state. Finally, we predict the transient formation of electronic Floquet bands in time-and angle-resolved photoemission spectroscopy experiments as a consequence of the proposed mechanism.

Authors:
; ; ; ;
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1375806
DOE Contract Number:
AC02-06CH11357
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review B; Journal Volume: 96; Journal Issue: 1
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY

Citation Formats

Babadi, Mehrtash, Knap, Michael, Martin, Ivar, Refael, Gil, and Demler, Eugene. Theory of parametrically amplified electron-phonon superconductivity. United States: N. p., 2017. Web. doi:10.1103/PhysRevB.96.014512.
Babadi, Mehrtash, Knap, Michael, Martin, Ivar, Refael, Gil, & Demler, Eugene. Theory of parametrically amplified electron-phonon superconductivity. United States. doi:10.1103/PhysRevB.96.014512.
Babadi, Mehrtash, Knap, Michael, Martin, Ivar, Refael, Gil, and Demler, Eugene. 2017. "Theory of parametrically amplified electron-phonon superconductivity". United States. doi:10.1103/PhysRevB.96.014512.
@article{osti_1375806,
title = {Theory of parametrically amplified electron-phonon superconductivity},
author = {Babadi, Mehrtash and Knap, Michael and Martin, Ivar and Refael, Gil and Demler, Eugene},
abstractNote = {Ultrafast optical manipulation of ordered phases in strongly correlated materials is a topic of significant theoretical, experimental, and technological interest. Inspired by a recent experiment on light-induced superconductivity in fullerenes [M. Mitrano et al., Nature (London) 530, 461 (2016)], we develop a comprehensive theory of light-induced superconductivity in driven electron-phonon systemswith lattice nonlinearities. In analogy with the operation of parametric amplifiers, we show how the interplay between the external drive and lattice nonlinearities lead to significantly enhanced effective electron-phonon couplings. We provide a detailed and unbiased study of the nonequilibrium dynamics of the driven system using the real-time Green's function technique. To this end, we develop a Floquet generalization of the Migdal-Eliashberg theory and derive a numerically tractable set of quantum Floquet-Boltzmann kinetic equations for the coupled electron-phonon system. We study the role of parametric phonon generation and electronic heating in destroying the transient superconducting state. Finally, we predict the transient formation of electronic Floquet bands in time-and angle-resolved photoemission spectroscopy experiments as a consequence of the proposed mechanism.},
doi = {10.1103/PhysRevB.96.014512},
journal = {Physical Review B},
number = 1,
volume = 96,
place = {United States},
year = 2017,
month = 7
}
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