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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.

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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