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arXiv · 2204.11029

Anisotropic terahertz optostriction in group-IV monochalcogenide compounds

Kun Liu·Jian Zhou
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Abstract

Terahertz (THz) technology is a cutting-edge scheme with various promising applications, such as next generation telecommunication, non-destructive evaluation, security check, and in-depth characterization, owing to their sensitivity to material geometric change and good transparency. Even though tremendous progresses have been made during the past decade, exploration the mechanisms of THz-matter interaction microscopically is still in its infancy. In this work, we use thermodynamic theory to show how THz illumination deforms materials and use group-IV monochalcogenide compounds to illustrate it. According to our first-principles density functional theory calculations, THz light with intermediate intensity (~109 W/cm2) could yield elastic deformations on the order of ~0.1%, depending on laser polarization direction. Large anisotropic opto-mechanical responses are also revealed. Finally, we show that such strain can be detected via measuring the layer-resolved shift current under a probe light irradiation.

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BibTeXRIS

Kun Liu, Jian Zhou. 2022-04-23. Anisotropic terahertz optostriction in group-IV monochalcogenide compounds. https://doi.org/10.1103/physrevb.105.195406

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