Phonon-mode couplings studied by pump-probe photoemission

ORAL

Abstract

Motivated by recent pump-probe photoemission experiments on cuprate superconductors, we show how the coupling of electrons to phonon modes at the same time leads to a prominent kink in the equilibrium band dispersion and to a distinct behavior of relaxation time scales in nonequilibrium experiments. Here, using the nonequilibrium solution of a model photoexcited electron-phonon system we show that the return of the electrons to equilibrium is governed by the equilibrium self-energy so that the phonon frequency sets a window for``slow'' versus ``fast'' relaxation. The overall structure of the relaxation spectroscopy in the time domain allows for a reliable and quantitative extraction of the electron-phonon coupling strength.

*This work was supported by the Department of Energy, Office of Basic Energy Research under Grants No. DE-FG02-08ER46542 (Georgetown), DE-AC02-76SF00515 (Stanford/SLAC), and DE- SC0007091 (for the collaboration).

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Authors

  • Michael Sentef

    • Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory
    • Stanford Institute for Materials and Energy Science (SIMES), SLAC National Accelerator Laboratory, Menlo Park, CA 94025, USA

  • Alexander Kemper

    • Lawrence Berkeley National Lab, 1 Cyclotron Road, Berkeley, CA 94720, USA

  • Brian Moritz

    • Department of Physics, Northern Illinois University, DeKalb, IL 60115, USA

  • James Freericks

    • Department of Physics, Georgetown University, Washington, DC 20057, USA

  • Zhi-Xun Shen

    • Stanford Institute for Materials and Energy Science (SIMES), SLAC National Accelerator Laboratory, Menlo Park, CA 94025, USA

  • Thomas Devereaux

    • Stanford Institute for Materials and Energy Science (SIMES), SLAC National Accelerator Laboratory, Menlo Park, CA 94025, USA