Photoinduced phase switching in 1T’-TaTe<sub>2</sub> visualized by relativistic ultrafast electron diffraction*

ORAL

Abstract

Optical quenching has been shown to induce phase transitions and reveal exotic “hidden” phases in quantum materials such as TaS2 and TaSe2, exposing potential for ultrafast switching applications and rendering it one of the forefront techniques for manipulation of such materials.

We investigated 1T’-TaTe2 - a member of the 2D TaX2 family with unique atomic ordering of Ta atoms including forming trimer superstructures below Tc ~ 170 K. We optically induced phase transition in 1T’-TaTe2 at 10 K and used the ultrafast electron diffraction facility at Lawrence Berkeley National Laboratory (HiRES [1]) to sensitively probe its structural response [2]. The system was found to switch on picosecond timescale between the trimer superstructure and the corresponding melted phase via a charge transfer mechanism according to density functional theory (DFT) calculations, opening up pathways to manipulate atomic order in this material.

In this contribution, we discuss the observed dynamics in light of dynamical diffraction simulations and DFT and provide an outlook for future studies of this intriguing system.

[1]. K. M. Siddiqui and D. B. Durham et al., arXiv:2009.02891 (2020).
[2]. F. Ji et al.,Commun Phys 2, 54, (2019).

**Work at LBNL was supported by the DOE Office of Basic Energy Sciences.

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Presenters

  • Khalid Siddiqui

    • Materials Sciences Division, Lawrence Berkeley National Laboratory

Authors

  • Khalid Siddiqui

    • Materials Sciences Division, Lawrence Berkeley National Laboratory

  • Daniel Brian Durham

    • National Center for Electron Microscopy, Lawrence Berkeley National Laboratory

  • Frederick Cropp

    • Department of Physics and Astronomy, University of California, Los Angeles

  • Sangeeta Rajpurohit

    • Lawrence Berkeley National Laboratory, USA
    • Molecular Foundry, Lawrence Berkeley National Laboratory

  • Colin Ophus

    • Molecular Foundry, Lawrence Berkeley National Laboratory
    • Lawrence Berkeley National Laboratory
    • LBNL
    • National Center for Electron Microscopy, Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA, USA

  • Yanglin Zhu

    • The Pennsylvania State University
    • Physics, Penn State University
    • Pennsylvania State University
    • Department of Physics, Pennsylvania State University
    • Department of Physics, The Pennsylvania State University
    • Physics, The Pennsylvania State University

  • Johan D Carlström

    • Molecular Foundry, Lawrence Berkeley National Laboratory

  • Camille Stavrakas

    • Molecular Foundry, Lawrence Berkeley National Laboratory

  • Zhiqiang Mao

    • Pennsylvania State University
    • Department of Physics, Penn State University
    • The Pennsylvania State University
    • Penn State University
    • Physics, Penn State University
    • Department of Physics, Pennsylvania State University
    • Department of Physics, The Pennsylvania State University
    • Physics, The Pennsylvania State University
    • Physics, Pennsylvania State University
    • Department of Materials Science and Engineering, Pennsylvania State University

  • Archana Raja

    • Molecular Foundry, Lawrence Berkeley National Laboratory

  • Pietro Musumeci

    • Department of Physics and Astronomy, University of California, Los Angeles

  • Liang Tan

    • Lawrence Berkeley National Laboratory
    • Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
    • Molecular Foundry, Lawrence Berkeley National Lab
    • Lawrence Berkeley National Laboratory, USA
    • Molecular Foundry, Lawrence Berkeley National Laboratory

  • Andrew M Minor

    • National Center for Electron Microscopy, Lawrence Berkeley National Laboratory
    • UC Berkeley

  • Robert A Kaindl

    • Materials Sciences Division, Lawrence Berkeley National Laboratory
    • Lawrence Berkeley National Laboratory
    • Department of Physics, Arizona State University
    • Physics, Arizona State University

  • Daniele Filippetto

    • Accelerator Technology and Applied Physics Division, Lawrence Berkeley National Laboratory