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arXiv · 2203.12834

Continuous-variable quantum sensing of a dissipative reservoir

Yi-Da Sha·Wei Wu
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Abstract

We propose a continuous-variable quantum sensing scheme, in which a harmonic oscillator is employed as the probe to estimate the parameters in the spectral density of a quantum reservoir, within a non-Markovian dynamical framework. It is revealed that the sensing sensitivity can be effectively boosted by (i) optimizing the weight of the momentum-position-type coupling in the whole probe-reservoir interaction Hamiltonian, (ii) the initial quantum squeezing resource provided by the probe, (iii) the noncanonical equilibration induced by the non-Markovian effect, and (iv) applying an external driving field. Our results may have some potential applications in understanding and controlling the decoherence of dissipative continuous-variable systems.

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Yi-Da Sha, Wei Wu. 2022-03-24. Continuous-variable quantum sensing of a dissipative reservoir. https://doi.org/10.1103/physrevresearch.4.023169

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