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arXiv · 2302.01953

Trapping microparticles in a structured dark focus

F. Almeida·I. Sousa·O. Kremer·B. Pinheiro da Silva·D. S. Tasca·A. Z. Khoury·G. Temporão·T. Guerreiro
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Abstract

We experimentally demonstrate stable trapping and controlled manipulation of silica microspheres in a structured optical beam consisting of a dark focus surrounded by light in all directions - the so-called Dark Focus Tweezer. Results from power spectrum and potential analysis demonstrate the non-harmonicity of the trapping potential landspace, which is reconstructed from experimental data in agreement to Lorentz-Mie numerical simulations. Applications of the dark tweezer in levitated optomechanics and biophysics are discussed.

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F. Almeida, I. Sousa, O. Kremer, B. Pinheiro da Silva, D. S. Tasca, A. Z. Khoury, G. Temporão, T. Guerreiro. 2023-02-03. Trapping microparticles in a structured dark focus. https://doi.org/10.1103/physrevlett.131.163601

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