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arXiv · 2503.15882

Optical control of the moir\'e twist angle

Zhiren He·Prathap Kumar Jharapla·Nicolas Leconte·Jeil Jung·Guru Khalsa
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Abstract

In this theoretical work, we propose an all-optical method for fast, precise manipulation of two-dimensional multilayers by transferring orbital angular momentum from phase-structured light (e.g. vortex beams) to a 2D material flake. We model the light-matter interaction, analyze the twist dynamics, and develop a phase diagram for optical twists by mapping the system onto an impulsively forced nonlinear pendulum. Our findings reveal rich dynamical responses spanning single- and multi-pulse twist angle control to (quasi)stable dynamical trajectories, and suggest a pathway for all-optical measurement of the twist potential energy. Aided by classical potential estimates for the interlayer energy and numerical simulation, we demonstrate the feasibility of this approach with hexagonal boron nitride bilayers and extend the results to dichalcogenides with first-principles calculations. These results can be generalized to other 2D multilayers, paving the way for scalable and customizable moir\'e electronics and photonics.

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Zhiren He, Prathap Kumar Jharapla, Nicolas Leconte, Jeil Jung, Guru Khalsa. 2025-03-20. Optical control of the moir\'e twist angle. https://arxiv.org/abs/2503.15882

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