Dynamical slowing down in an ultrafast photo-induced phase transition

ORAL

Abstract

Complex systems, which consist of a large number of interacting constituents, often exhibit universal behavior near a phase transition. A slowdown of certain dynamical observables is one such recurring feature found in a vast array of contexts. This phenomenon, known as critical slowing down, is well studied mostly in thermodynamic phase transitions. However, it is less understood in highly nonequilibrium settings, where the time it takes to traverse the phase boundary becomes comparable to the timescale of dynamical fluctuations. Using transient optical spectroscopy and femtosecond electron diffraction, we studied a photo-induced transition of a model charge-density-wave (CDW) compound, LaTe3. We observed that it takes the longest time to suppress the order parameter at the threshold photoexcitation density, where the CDW transiently vanishes. This finding can be quantitatively captured by generalizing the time-dependent Landau theory to a system far from equilibrium. The experimental observation and theoretical understanding of dynamical slowing down may offer insight into other general principles behind nonequilibrium phase transitions in many-body systems.

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Presenters

  • Alfred Zong

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

Authors

  • Alfred Zong

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

  • Anshul Kogar

    Physics, Massachusetts Institute of Technology, Massachusetts Institute of Technology

  • Pavel E Dolgirev

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

  • Emre Ergecen

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

  • Mehmet B Yilmaz

    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

  • I-Cheng Tung

    Argonne National Laboratory

  • Joshua Straquadine

    Physics, Stanford University, Stanford University

  • Philip Walmsley

    Physics, Stanford University, Stanford University

  • Xiaozhe Shen

    SLAC National Accelerator Laboratory

  • Jie Yang

    SLAC National Accelerator Laboratory

  • Renkai Li

    SLAC National Accelerator Laboratory

  • Suji Park

    SLAC National Accelerator Laboratory

  • Matthias C Hoffmann

    SLAC National Accelerator Laboratory

  • Benjamin K Ofori-Okai

    SLAC National Accelerator Laboratory

  • Michael E Kozina

    SLAC National Accelerator Laboratory

  • Haidan Wen

    Argonne National Laboratory, Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439, USA, X-ray Science Division,, Argonne National Laboratory

  • Xijie Wang

    SLAC National Accelerator Laboratory, SLAC

  • 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

  • Nuh Gedik

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