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arXiv · 2308.16502

Apply Non-Hermitian Physics to Realize Ultra-High-Quality Factors of Optically Trapped Particles

Yang Li·Xiao Li
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Abstract

Optical trapping and binding systems are non-Hermitian. On one hand, the optical force is non-Hermitian and may pump energy into the trapped particle when the non-Hermiticity is sufficiently large. On the other hand, the ambient damping constitutes a loss to the particle. Here, we show that in a low-friction environment, the interplay between the energy pumped-in by light and the ambient dissipation can give rise to either instability or a periodic vibration characterized by a finite quality factor (Q-factor). Through a comprehensive exploration, we analyze the influence of various parameters on the non-Hermitian force field. Our investigation reveals several strategies for enhancing the non-Hermitian force field, such as augmenting particle radius and refractive index, utilizing triangular lattice optical clusters, and reducing lattice constants.

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Yang Li, Xiao Li. 2023-08-31. Apply Non-Hermitian Physics to Realize Ultra-High-Quality Factors of Optically Trapped Particles. https://arxiv.org/abs/2308.16502

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