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Continuous Wave Sum Frequency Generation and Imaging of Monolayer and Heterobilayer 2D Semiconductors

ORAL

Abstract

Optical nonlinearities in two-dimensional transition metal dichalcogenides (TMDs) are greatly enhanced by excitonic resonances. Here we report continuous-wave second harmonic and sum frequency generation from two-dimensional TMD monolayers and their heterostructures, with pump irradiances several orders of magnitude lower than conventional pulsed experiments. The high nonlinear efficiency originates from above-gap excitons in the band nesting regions, as revealed by wavelength-dependent second order optical susceptibilities quantified in four common monolayer transition metal dichalcogenides. Using sum frequency excitation spectroscopy and imaging, we identify and distinguish one- and two-photon resonances in both monolayers and heterobilayers. Data for heterostructures reveal responses from constituent layers accompanied with nonlinear signal correlated with interlayer transitions. Furthermore, we demonstrate spatial mapping of heterogeneous interlayer coupling by sum frequency and second harmonic confocal microscopy on heterobilayer MoSe2/WSe2.

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Presenters

  • Kaiyuan Yao

    Columbia University, Mechanical Engineering, Columbia University

Authors

  • Kaiyuan Yao

    Columbia University, Mechanical Engineering, Columbia University

  • Emanuil Yanev

    Columbia University, Mechanical Engineering, Columbia University

  • Hsun jen Chuang

    United States Naval Research Laboratory, naval research laboratory

  • Matthew Rosenberger

    National Research Council, US Naval Research Laboratory, Washington, DC 20375, United States Naval Research Laboratory, naval research laboratory

  • Xinyi Xu

    Mechanical Engineering, Columbia University, Columbia University

  • Thomas Darlington

    Columbia University, University of California, Berkeley, Mechanical Engineering, Columbia University

  • Kathleen M McCreary

    United States Naval Research Laboratory, naval research laboratory, Naval Research Lab

  • Aubrey T. Hanbicki

    United States Naval Research Laboratory/ Laboratory for Physical Sciences, naval research laboratory, Laboratory for Physical Sciences, University of Maryland, LPS

  • Berend Thomas Jonker

    United States Naval Research Laboratory, naval research laboratory, Naval Research Lab

  • Xiaoyang Zhu

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

  • Dmitri Basov

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

  • P. James Schuck

    Columbia University, Mechanical Engineering, Columbia University