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Published on: May 30, 2014
Variational quantum metrology for multiparameter estimation under dephasing noise
Trung Kien Le1,2, Hung Q Nguyen3, Le Bin Ho4,5
1Department of Physics, University of California, Santa Barbara, Santa Barbara, USA.
Abstract:
We present a hybrid quantum-classical variational scheme to enhance precision in quantum metrology. In the scheme, both the initial state and the measurement basis in the quantum part are parameterized and optimized via the classical part. It enables the maximization of information gained about the measured quantity. We discuss specific applications to 3D magnetic field sensing under several dephasing noise models. Indeed, we demonstrate its ability to simultaneously estimate all parameters and surpass the standard quantum limit, making it a powerful tool for metrological applications.
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