Quantum Back Action Evasion with Reservoir Engineering

Yohei Nishino; James W. Gardner; Yanbei Chen; Kentaro Somiya

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arXiv · 2505.01013

Quantum Back Action Evasion with Reservoir Engineering

Yohei Nishino·James W. Gardner·Yanbei Chen·Kentaro Somiya

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Abstract

We propose a back-action evading scheme for a free mass that combines reservoir engineering with velocity measurement. The underlying principle follows the double-pass-type speed meter, which measures the mirror's velocity using a nonreciprocal interaction. In our method, the nonreciprocal coupling is realized through reservoir engineering, following the recipe proposed in [Phys. Rev. X 5, 021025]. We show that reservoir engineering can reproduce the double-pass speed meter with optimal feedforward, using only reciprocal interactions. The resulting force sensitivity surpasses the standard quantum limit, providing an alternative route to quantum back-action evasion in cavity optomechanical systems.

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Yohei Nishino, James W. Gardner, Yanbei Chen, Kentaro Somiya. 2025-05-02. Quantum Back Action Evasion with Reservoir Engineering. https://arxiv.org/abs/2505.01013

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