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Enhanced Parameter Estimation with Periodically Driven Quantum Probe

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 Added by Peter Ivanov
 Publication date 2021
  fields Physics
and research's language is English




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We propose a quantum metrology protocol for measuring frequencies and weak forces based on a periodic modulating quantum Jahn-Teller system composed of a single spin interacting with two bosonic modes. We show that in the first order of the frequency drive the time-independent effective Hamiltonian describes spin-dependent interaction between the two bosonic modes. In the limit of high-frequency drive and low bosonic frequency the quantum Jahn-Teller system exhibits critical behaviour which can be used for high-precision quantum estimation. A major advantage of our scheme is the robustness of the system against spin decoherence which allows to perform parameter estimations with measurement time not limited by spin dephasing.



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