Theory of parametrically amplified electronphonon 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 lightinduced superconductivity in fullerenes [M. Mitrano et al., Nature (London) 530, 461 (2016)], we develop a comprehensive theory of lightinduced superconductivity in driven electronphonon 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 electronphonon couplings. We provide a detailed and unbiased study of the nonequilibrium dynamics of the driven system using the realtime Green's function technique. To this end, we develop a Floquet generalization of the MigdalEliashberg theory and derive a numerically tractable set of quantum FloquetBoltzmann kinetic equations for the coupled electronphonon 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 timeand angleresolved 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) (SC22)
 OSTI Identifier:
 1375806
 DOE Contract Number:
 AC0206CH11357
 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 electronphonon 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 electronphonon 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 electronphonon superconductivity". United States.
doi:10.1103/PhysRevB.96.014512.
@article{osti_1375806,
title = {Theory of parametrically amplified electronphonon 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 lightinduced superconductivity in fullerenes [M. Mitrano et al., Nature (London) 530, 461 (2016)], we develop a comprehensive theory of lightinduced superconductivity in driven electronphonon 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 electronphonon couplings. We provide a detailed and unbiased study of the nonequilibrium dynamics of the driven system using the realtime Green's function technique. To this end, we develop a Floquet generalization of the MigdalEliashberg theory and derive a numerically tractable set of quantum FloquetBoltzmann kinetic equations for the coupled electronphonon 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 timeand angleresolved 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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