Sub-wavelength optical lattice in 2D materials

Supratik Sarkar; Mahmoud Jalali Mehrabad; Daniel G. Suárez-Forero; Liuxin Gu; Christopher J. Flower; Lida Xu; Kenji Watanabe; Takashi Taniguchi; Suji Park; Houk Jang; You Zhou; Mohammad Hafezi

arXiv · 2406.00464

Sub-wavelength optical lattice in 2D materials

Supratik Sarkar·Mahmoud Jalali Mehrabad·Daniel G. Suárez-Forero·Liuxin Gu·Christopher J. Flower·Lida Xu·Kenji Watanabe·Takashi Taniguchi·Suji Park·Houk Jang·You Zhou·Mohammad Hafezi

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Abstract

Recently, light-matter interaction has been vastly expanded as a control tool for inducing and enhancing many emergent non-equilibrium phenomena. However, conventional schemes for exploring such light-induced phenomena rely on uniform and diffraction-limited free-space optics, which limits the spatial resolution and the efficiency of light-matter interaction. Here, we overcome these challenges using metasurface plasmon polaritons (MPPs) to form a sub-wavelength optical lattice. Specifically, we report a ``non-local" pump-probe scheme where MPPs are excited to induce a spatially modulated AC Stark shift for excitons in a monolayer of MoSe$_2$, several microns away from the illumination spot. Remarkably, we identify nearly two orders of magnitude reduction for the required modulation power compared to the free-space optical illumination counterpart. Moreover, we demonstrate a broadening of the excitons' linewidth as a robust signature of MPP-induced periodic sub-diffraction modulation. Our results will allow exploring power-efficient light-induced lattice phenomena below the diffraction limit in active chip-compatible MPP architectures.

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Supratik Sarkar, Mahmoud Jalali Mehrabad, Daniel G. Suárez-Forero, Liuxin Gu, Christopher J. Flower, Lida Xu, Kenji Watanabe, Takashi Taniguchi, Suji Park, Houk Jang, You Zhou, Mohammad Hafezi. 2024-06-01. Sub-wavelength optical lattice in 2D materials. https://arxiv.org/abs/2406.00464

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