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arXiv · 2201.03918

Quantum non-demolition measurements of moving target states

A. L. Andersen·K. Mølmer
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Abstract

We present a protocol for probing the state of a quantum system by its resonant coupling and entanglement with a meter system. By continuous measurement of a time evolving meter observable, we infer the evolution of the entangled systems and, ultimately, the state and dynamics of the system of interest. The photon number in a cavity field is thus resolved by simulated monitoring of the time dependent excited state population of a resonantly coupled two-level system, and we propose to regard this as an extension of quantum non-demolition measurements with potential applications in quantum metrology and quantum computing.

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A. L. Andersen, K. Mølmer. 2022-01-11. Quantum non-demolition measurements of moving target states. https://doi.org/10.1103/physrevlett.129.120402

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