Probe optimization for quantum metrology via closed-loop learning
control
- URL: http://arxiv.org/abs/2006.09730v2
- Date: Tue, 21 Jul 2020 04:49:04 GMT
- Title: Probe optimization for quantum metrology via closed-loop learning
control
- Authors: Xiaodong Yang, Jayne Thompson, Ze Wu, Mile Gu, Xinhua Peng, Jiangfeng
Du
- Abstract summary: We propose a practical controlled sequential scheme for quantum metrology.
Purity loss of the probe state, which relates to quantum Fisher information, is measured efficiently as the fitness to guide the learning loop.
- Score: 11.156127985996417
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: Experimentally achieving the precision that standard quantum metrology
schemes promise is always challenging. Recently, additional controls were
applied to design feasible quantum metrology schemes. However, these approaches
generally does not consider ease of implementation, raising technological
barriers impeding its realization. In this paper, we circumvent this problem by
applying closed-loop learning control to propose a practical controlled
sequential scheme for quantum metrology. Purity loss of the probe state, which
relates to quantum Fisher information, is measured efficiently as the fitness
to guide the learning loop. We confirm its feasibility and certain
superiorities over standard quantum metrology schemes by numerical analysis and
proof-of-principle experiments in a nuclear magnetic resonance (NMR) system.
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