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Optimizing Passive Quantum Clocks



Michael J. Mullan, Emanuel Knill


We describe protocols for passive atomic clocks based onquantum interrogation of the atoms. Unlike previous techniques, our protocols are adaptive and take advantage of prior information about the clock's state. To reduce deviations from an ideal clock, each interrogation is optimized by means of a semidefinite program for atomic state preparation and measurement whose objective function depends on the prior information. Our knowledge of the clock's state is maintained according to a Bayesian model that accounts for noise and measurement results. We implement a full simulation of a running clock with power-law noise models and find significant improvements by applying our techniques.
Physical Review A


heisenberg limit, semidefinite programming, quantum logic clocks, standard quantum limit


Mullan, M. and Knill, E. (2014), Optimizing Passive Quantum Clocks, Physical Review A, [online], (Accessed July 22, 2024)


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Created October 7, 2014, Updated October 12, 2021