Related papers: Reference-frame-independent quantum metrology

Reference-frame-independent quantum metrology

URL: http://arxiv.org/abs/2410.10518v1
Date: Mon, 14 Oct 2024 13:59:08 GMT
Title: Reference-frame-independent quantum metrology
Authors: Satoya Imai, Otfried Gühne, Géza Tóth,
Abstract summary: We present systematic methods for conducting nonlinear quantum metrology in scenarios lacking a common reference frame. We derive the metrological precision using an error propagation formula based solely on local unitary invariants. We analyze our results in the context of local decoherence and discuss its influences on the observed scaling.
Score: 0.0
License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Abstract: How can we perform a metrological task if only limited control over a quantum system is given? Here, we present systematic methods for conducting nonlinear quantum metrology in scenarios lacking a common reference frame. Our approach involves preparing multiple copies of quantum systems and then performing local measurements with randomized observables. First, we derive the metrological precision using an error propagation formula based solely on local unitary invariants, which are independent of the chosen basis. Next, we provide analytical expressions for the precision scaling in various examples of nonlinear metrology involving two-body interactions, like the one-axis twisting Hamiltonian. Finally, we analyze our results in the context of local decoherence and discuss its influences on the observed scaling.

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