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arXiv · 2411.04980

Quantum limited imaging of a nanomechanical resonator with a spatial mode sorter

Morgan Choi·Christian Pluchar·Wenhua He·Saikat Guha·Dalziel Wilson
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Abstract

We explore the use of a spatial mode sorter to image a nanomechanical resonator, with the goal of studying the quantum limits of active imaging and extending the toolbox for optomechanical force sensing. In our experiment, we reflect a Gaussian laser beam from a vibrating nanoribbon and pass the reflected beam through a commercial spatial mode demultiplexer (Cailabs Proteus). The intensity in each demultiplexed channel depends on the mechanical mode shapes and encodes information about their displacement amplitudes. As a concrete demonstration, we monitor the angular displacement of the ribbon's fundamental torsion mode by illuminating in the fundamental Hermite-Gauss mode (HG$_{00}$) and reading out in the HG$_{01}$ mode. We show that this technique permits readout of the ribbon's torsional vibration with a precision near the quantum limit. Our results highlight new opportunities at the interface of quantum imaging and quantum optomechanics.

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quant-phcond-mat.mes-hallphysics.app-phphysics.optics

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Morgan Choi, Christian Pluchar, Wenhua He, Saikat Guha, Dalziel Wilson. 2024-11-07. Quantum limited imaging of a nanomechanical resonator with a spatial mode sorter. https://doi.org/10.1103/6msj-wh2f

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