Evidence for Topological Defects in a Photoinduced Charge Density Wave Transition

 · Invited

Abstract

Upon excitation with an intense laser pulse, a symmetry-broken ground state can undergo a non-equilibrium phase transition through pathways different from those in thermal equilibrium. The mechanism underlying these photoinduced phase transitions has long been researched in the study of condensed matter systems, but many details in this ultrafast, non-adiabatic regime still remain to be clarified. To this end, we investigate the light-induced melting of a unidirectional charge density wave (CDW) in LaTe3. Using a suite of time-resolved probes, we independently track the amplitude and phase dynamics of the CDW. We find that a fast (approximately 1 picosecond) recovery of the CDW amplitude is followed by a slower re-establishment of phase coherence. This longer timescale is dictated by the presence of topological defects: long-range order is inhibited and is only restored when the defects annihilate.

*We acknowledge support from the US Department of Energy, BES DMSE (experimental setup and data acquisition), from the Gordon and Betty Moore Foundation’s EPiQS Initiative grant GBMF4540 (data analysis), the Army Research Office (equipment support for the tr-ARPES), and the Skoltech NGP Program (Skoltech-MIT joint project) (theory). Y.-Q.B. and P.J.-H. acknowledge support from the Center for Excitonics, an Energy Frontier Research Center funded by the US Department of Energy, Office of Science, Office of Basic Energy Sciences, under award number DESC0001088, as well as the Gordon and Betty Moore Foundation’s EPiQS Initiative through grant GBMF4541 (sample preparation and characterization). Work at Stanford was supported by the US Department of Energy, Office of Basic Energy Sciences, under contract number DE-AC02-76SF00515 (sample growth and characterization). P.W. was supported in part by the Gordon and Betty Moore Foundation’s EPiQS Initiative through grant GBMF4414. E.B. acknowledge

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Presenters

  • Anshul Kogar

    • Physics, Massachusetts Institute of Technology
    • Massachusetts Institute of Technology

Authors

  • Anshul Kogar

    • Physics, Massachusetts Institute of Technology
    • Massachusetts Institute of Technology

  • Alfred Zong

    • Physics, Massachusetts Institute of Technology
    • Department of Physics, Massachusetts Institute of Technology
    • Massachusetts Institute of Technology

  • Ya-Qing Bie

    • Physics, Massachusetts Institute of Technology
    • Massachusetts Institute of Technology

  • Timm Rohwer

    • Physics, Massachusetts Institute of Technology
    • Massachusetts Institute of Technology

  • Changmin Lee

    • Physics, Massachusetts Institute of Technology
    • Massachusetts Institute of Technology
    • Department of Physics, Massachusetts Institute of Technology

  • Edoardo Baldini

    • Physics, Massachusetts Institute of Technology
    • Massachusetts Institute of Technology
    • Department of Physics, Massachusetts Institute of Technology

  • Emre Ergecen

    • Physics, Massachusetts Institute of Technology
    • Department of Physics, Massachusetts Institute of Technology
    • Massachusetts Institute of Technology

  • Mehmet B Yilmaz

    • Physics, Massachusetts Institute of Technology
    • Department of Physics, Massachusetts Institute of Technology

  • Byron Kendall Freelon

    • Physics, Massachusetts Institute of Technology

  • Edbert Jarvis Sie

    • Physics, Massachusetts Institute of Technology
    • Department of Materials Science and Engineering, Stanford University
    • Stanford University

  • Hengyun Zhou

    • Physics, Massachusetts Institute of Technology
    • Harvard University
    • Department of Physics, Harvard University

  • Joshua Straquadine

    • Physics, Stanford University
    • Stanford University

  • Philip Walmsley

    • Physics, Stanford University
    • Stanford University

  • Pavel E Dolgirev

    • Physics, Skolkovo Institute of Science and Technology
    • Skolkovo Institute of Science and Technology

  • Alexander Rozhkov

    • Physics, Skolkovo Institute of Science and Technology

  • Ian R Fisher

    • Physics, Stanford University
    • Applied Physics, Stanford University
    • Stanford University
    • Pulsed Field Faclity, National High Magnetic Field Laboratory

  • Pablo Jarillo-Herrero

    • Physics, Massachusetts Institute of Technology
    • Department of Physics, Massachusetts Institute of Technology
    • Massachusetts Institute of Technology
    • Dept. of Physics, Massachusetts Institute of Technology, USA
    • Massachusetts Inst of Tech-MIT
    • Physics, MIT

  • Boris V. Fine

    • Physics, Skolkovo Institute of Science and Technology
    • Center for Photonics and Quantum Materials, Skolkovo Institute of Science and Technology

  • Nuh Gedik

    • Physics, Massachusetts Institute of Technology
    • Massachusetts Inst of Tech-MIT
    • Massachusetts Institute of Technology
    • Department of Physics, Massachusetts Institute of Technology