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arXiv · 2601.13415

Precise estimation of the coupling strength between two nanomechanical modes from four Ramsey fringes

Anh Tuan Le·Avishek Chowdhury·Hugo Ribeiro·Eva M. Weig
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Abstract

We experimentally determine the coupling strength between two strongly coupled nanomechanical modes using a Ramsey-inspired technique optimized for signals as short as four fringes. The method is applied to precisely probe the change of the coupling rate induced by a modification of the microwave-cavity readout field. It opens a pathway towards sensing electrostatic field fluctuations approaching single-charge resolution.

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Anh Tuan Le, Avishek Chowdhury, Hugo Ribeiro, Eva M. Weig. 2026-01-19. Precise estimation of the coupling strength between two nanomechanical modes from four Ramsey fringes. https://arxiv.org/abs/2601.13415

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