Ultrafast exciton dynamics in WSe<sub>2 </sub>optical waveguides

ORAL

Abstract

We investigated dynamics of excitons in a Van der Waals Semiconducting, WSe2, waveguide. We monitored the electric-field profile of waveguided infrared radiation under intense femtosecond photo-excitation in real space and time. Drastic modifications of the complex wavevector of guided radiation were observed. The non-equilibrium energy momentum dispersion relationship implicates excitons in the photo-induced transformations. Unprecedented coherent dynamics of refraction, on the sub-ps timescale, reveal an optical stark-shift of the A-exciton resonance. Our study establishes that excitons enhance the performance of vdW optical modulators providing a tuning knob unavailable in conventional III-V semiconducting platforms. Our transient images and first-principles theoretical calculations establish fundamental limits of excitons in WSe2optical modulators.

*Support by Programmable Quantum Materials, an Energy Frontier Research Center funded by the U.S. Department of Energy (DOE), Office of Science, Basic Energy Sciences (BES), under award DE-SC0019443”, the European Research Council (ERC-2015-AdG694097), the Cluster of Excellence 'Advanced Imaging of Matter' (AIM), the Flatiron Institute, a division of the Simons Foundation, and the Alexander von Humboldt foundation are acknowledged.

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Presenters

  • Aaron Sternbach

    • Columbia Univ
    • Department of Physics, Columbia University
    • Physics, Columbia University

Authors

  • Aaron Sternbach

    • Columbia Univ
    • Department of Physics, Columbia University
    • Physics, Columbia University

  • Simone Latini

    • Max Planck Institute for Structure and Dynamics of Matter
    • Max Planck Institute for the Structure and Dynamics of Matter

  • Sanghoon Chae

    • Columbia University
    • Mechanical Engineering, Columbia University

  • Hannes Huebener

    • Max Planck Institute for the Structure and Dynamics of Matter
    • Max Planck Institute for the Structure and Dynamics of Matter, Luruper Chaussee 149, 22761 Hamburg, Germany

  • Umberto De Giovannini

    • Max Planck Institute for the Structure and Dynamics of Matter, Luruper Chaussee 149, 22761 Hamburg, Germany
    • Max Planck Institute for the Structure and Dynamics of Matter
    • Max Planck Inst Structure & Dynamics of Matter

  • Yinming Shao

    • Physics, Columbia University
    • Department of Physics, Columbia University
    • Columbia University

  • Lin Xiong

    • Columbia Univ
    • Columbia University
    • Department of Physics, Columbia University
    • Physics, Columbia University

  • Zhiyuan Sun

    • Columbia Univ
    • Columbia University
    • Physics, Columbia University

  • Norman Shi

    • Physics, Columbia University

  • Peter Kissin

    • Physics, University of California, San Diego
    • University of California, San Diego

  • Guangxin Ni

    • Columbia University
    • Physics, Columbia University

  • Daniel A Rhodes

    • Columbia University
    • Columbia Univ
    • Mechanical Engineering, Columbia University
    • Columbia University, NY, USA
    • Department of Mechanical Engineering, Columbia University

  • Brian S Y Kim

    • Columbia University, The Department of Mechanical Engineering
    • Mechanical Engineering, Columbia University
    • Department of Mechanical Engineering, Columbia University

  • Nanfang Yu

    • Physics, Columbia University

  • Andrew Millis

    • Columbia Univ
    • Center for Computational Quantum Physics, The Flatiron Institute
    • Columbia University
    • Physics, Columbia University
    • Department of Physics, Columbia University
    • Center for Computational Quantum Physics, Flatiron Institute
    • Department of Physics, Columbia University, Center for Computational Quantum Physics, Flatiron Institute
    • Physics/CCQ, Columbia University and Flatiron Institute

  • Michael M Fogler

    • University of California San Diego
    • University of California, San Diego
    • UC San Diego
    • Physics, University of California, San Diego

  • P. James Schuck

    • Columbia University
    • Mechanical Engineering, Columbia University

  • Michal Lipson

    • Department of Electrical Engineering, Columbia University

  • Xiaoyang Zhu

    • Columbia Univ
    • Chemistry, Columbia University
    • Columbia University, Chemistry
    • Columbia University
    • Department of Chemistry, Columbia University

  • James C Hone

    • Columbia University
    • Mechanical Engineering, Columbia University
    • Columbia Univ
    • Physics, Columbia University
    • Columbia University, NY, USA
    • Department of Mechanical Engineering, Columbia University

  • Richard Averitt

    • Physics, University of California, San Diego
    • Physics, University Of California, San Diego
    • University of California, San Diego

  • Angel Rubio

    • Theory Department, Max Planck Institute for the Structure and Dynamics of Matter
    • Center for Computational Quantum Physics (CCQ), The Flatiron Institute
    • Max Planck Institute for Structure and Dynamics of Matter
    • Department of Physics, Columbia University, New York, New York 10027, USA
    • Max Planck Institute for the Structure and Dynamics of Matter, Hamburg, Germany
    • Max Planck Institute for the Structure and Dynamics of Matter
    • Structure and Dynamics of Matter, Max Planck Institute
    • Max Planck Institute for the Structure and Dynamics of Matter, Luruper Chaussee 149, 22761 Hamburg, Germany
    • Max Planck Inst Structure & Dynamics of Matter
    • Max Planck Institue for the Structure and Dynamics of Matter
    • Theory, Max Planck Institute for the Structure & Dynamics of Matter

  • Dmitri Basov

    • Columbia University, The Department of Physics
    • Columbia University
    • Physics, Columbia University
    • Columbia Univ
    • Department of Physics, Columbia University