- Letter
- Open Access
Quantum-limited imaging of a nanomechanical resonator with a spatial mode sorter
Phys. Rev. Research 7, L032031 – Published 8 August, 2025
DOI: https://doi.org/10.1103/6msj-wh2f
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 modeshapes 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 () and reading out in the 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.
Physics Subject Headings (PhySH)
Corrections
6 November, 2025
Correction: An incorrect version of Figure 2 was used for publication and has now been replaced with the correct version.
Article Text
Supplemental Material
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