Enhancement of the metrological sensitivity limit through knowledge of the average energy
arXiv:1908.11081 · doi:10.1103/PhysRevA.100.032114
Abstract
We consider the problem of quantum phase estimation with access to arbitrary measurements in a single suboptimal basis. The achievable sensitivity limit in this case is determined by the classical Cramér-Rao bound with respect to the fixed basis. Here we show that the sensitivity can be enhanced beyond this limit if knowledge about the energy expectation value is available. The combined information is shown to be equivalent to a direct measurement of an optimal linear combination of the basis projectors and the phase-imprinting Hamiltonian. Application to an atomic clock with oversqueezed spin states yields a sensitivity gain that scales linearly with the number of atoms. Our analysis further reveals that small modifications of the observable can have a strong impact on the sensitivity.
arXiv comment7 pages, 1 figure
References in corpus (30)
- Advances in Quantum Metrology
- Quantum metrology
- Entanglement detection
- Quantum metrology with nonclassical states of atomic ensembles
- On the Improvement of Frequency Stardards with Quantum Entanglement
- Many-particle entanglement with Bose--Einstein condensates
- General framework for estimating the ultimate precision limit in noisy quantum-enhanced metrology
- Entanglement, Non-linear Dynamics, and the Heisenberg Limit
- Quantum spin squeezing
- Quantum metrology from a quantum information science perspective
- The elusive Heisenberg limit in quantum enhanced metrology
- Fisher information and multiparticle entanglement
- Multipartite entanglement and high precision metrology
- Entanglement and Extreme Spin Squeezing
- Quantum Theory of Superresolution for Two Incoherent Optical Point Sources
- Spin squeezing and entanglement
- Noisy metrology beyond the standard quantum limit
- Optimal measurements for simultaneous quantum estimation of multiple phases
- The ultimate precision limits for noisy frequency estimation
- Sensitivity Bounds for Multiparameter Quantum Metrology
- Discontinuities of the quantum Fisher information and the Bures metric
- Metrological Nonlinear Squeezing Parameter
- Efficient entanglement criteria for discrete, continuous, and hybrid variables
- Frequentist and Bayesian Quantum Phase Estimation
- On the discontinuity of the quantum Fisher information for quantum statistical models with parameter dependent rank
- Characterizing the multipartite continuous-variable entanglement structure from squeezing coefficients and the Fisher information
- Tighter quantum uncertainty relations follow from a general probabilistic bound
- Entanglement and squeezing in continuous-variable systems
- Resolution-enhanced entanglement detection
- Estimation of general Hamiltonian parameters via controlled energy measurements