Squeezed reservoir engineering is a powerful technique in quantum information that combines the features of squeezing and reservoir engineering to create and stabilize non-classical quantum states. In this paper, we f...Squeezed reservoir engineering is a powerful technique in quantum information that combines the features of squeezing and reservoir engineering to create and stabilize non-classical quantum states. In this paper, we focus on the previously neglected aspect of the impact of the squeezing phase on the precision of quantum phase and amplitude estimation based on a simple model of a two-level system(TLS) interacting with a squeezed reservoir. We derive the optimal squeezed phase-matching conditions for phase φ and amplitude θ parameters, which are crucial for enhancing the precision of quantum parameter estimation. The robustness of the squeezing-enhanced quantum Fisher information against departures from these conditions is examined, demonstrating that minor deviations from phase-matching can still result in remarkable precision of estimation. Additionally, we provide a geometric interpretation of the squeezed phase-matching conditions from the classical motion of a TLS on the Bloch sphere. Our research contributes to a deeper understanding of the operational requirements for employing squeezed reservoir engineering to advance quantum parameter estimation.展开更多
We investigate quantum parameter estimation based on linear and Kerr-type nonlinear controls in an open quantum system, and consider the dissipation rate as an unknown parameter. We show that while the precision of pa...We investigate quantum parameter estimation based on linear and Kerr-type nonlinear controls in an open quantum system, and consider the dissipation rate as an unknown parameter. We show that while the precision of parameter estimation is improved,it usually introduces a significant deformation to the system state. Moreover, we propose a multi-objective model to optimize the two conflicting objectives:(1) maximizing the Fisher information, improving the parameter estimation precision, and(2)minimizing the deformation of the system state, which maintains its fidelity. Finally, simulations of a simplified ε-constrained model demonstrate the feasibility of the Hamiltonian control in improving the precision of the quantum parameter estimation.展开更多
A novel scheme is proposed to estimate three environmental parameters,the detuning,the temperature and the squeezing strength with one-qubit or two-qubit probes.Quantum Fisher information and the fidelity of the atom ...A novel scheme is proposed to estimate three environmental parameters,the detuning,the temperature and the squeezing strength with one-qubit or two-qubit probes.Quantum Fisher information and the fidelity of the atom probes are calculated.When the detuning between the frequency of cavity field and the atomic transition frequency is estimated,the dynamics of quantum Fisher information shows oscillatory and rising behaviors.To estimate the temperature of the thermal reservoir,the one-qubit probe with the superposition initial state is more favorable than the two-qubit probe with the entangled initial state.When the squeezing strength of the squeezed vacuum reservoir is estimated,we find that the estimation precision is significantly improved by utilizing the two-qubit probe with the maximal entangled initial state.Our work provides a potential application in the open quantum system and quantum information processing.展开更多
Simultaneously optimizing the estimation of the centroid and separation of two incoherent optical point sources is constrained by a tradeoff relation determined by an incompatibility coefficient.At the Rayleigh distan...Simultaneously optimizing the estimation of the centroid and separation of two incoherent optical point sources is constrained by a tradeoff relation determined by an incompatibility coefficient.At the Rayleigh distance,the incompatibility coefficient vanishes and thus the tradeoff relation no longer restricts the simultaneous optimization of measurement for a joint estimation.We construct such a joint optimal measurement by an elaborated analysis on the operator algebra of the symmetric logarithmic derivative.Our work not only confirms the existence of a joint optimal measurement for this specific imaging model,but also gives a promising method to characterize the condition on measurement compatibility for general multiparameter estimation problems.展开更多
基金Project supported by the National Natural Science Foundation of China (Grant No. 12265004)Jiangxi Provincial Natural Science Foundation (Grant No. 20242BAB26010)+1 种基金the National Natural Science Foundation of China (Grant No. 12365003)Jiangxi Provincial Natural Science Foundation (Grant Nos. 20212ACB211004 and 20212BAB201014)。
文摘Squeezed reservoir engineering is a powerful technique in quantum information that combines the features of squeezing and reservoir engineering to create and stabilize non-classical quantum states. In this paper, we focus on the previously neglected aspect of the impact of the squeezing phase on the precision of quantum phase and amplitude estimation based on a simple model of a two-level system(TLS) interacting with a squeezed reservoir. We derive the optimal squeezed phase-matching conditions for phase φ and amplitude θ parameters, which are crucial for enhancing the precision of quantum parameter estimation. The robustness of the squeezing-enhanced quantum Fisher information against departures from these conditions is examined, demonstrating that minor deviations from phase-matching can still result in remarkable precision of estimation. Additionally, we provide a geometric interpretation of the squeezed phase-matching conditions from the classical motion of a TLS on the Bloch sphere. Our research contributes to a deeper understanding of the operational requirements for employing squeezed reservoir engineering to advance quantum parameter estimation.
基金supported by the National Natural Science Foundation of China(Grant No.11404113)the Guangzhou Key Laboratory of Brain Computer Interaction and Applications(Grant No.201509010006)
文摘We investigate quantum parameter estimation based on linear and Kerr-type nonlinear controls in an open quantum system, and consider the dissipation rate as an unknown parameter. We show that while the precision of parameter estimation is improved,it usually introduces a significant deformation to the system state. Moreover, we propose a multi-objective model to optimize the two conflicting objectives:(1) maximizing the Fisher information, improving the parameter estimation precision, and(2)minimizing the deformation of the system state, which maintains its fidelity. Finally, simulations of a simplified ε-constrained model demonstrate the feasibility of the Hamiltonian control in improving the precision of the quantum parameter estimation.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.91536115 and 11534008)Natural Science Foundation of Shaanxi Province,China(Grant No.2016JM1005)。
文摘A novel scheme is proposed to estimate three environmental parameters,the detuning,the temperature and the squeezing strength with one-qubit or two-qubit probes.Quantum Fisher information and the fidelity of the atom probes are calculated.When the detuning between the frequency of cavity field and the atomic transition frequency is estimated,the dynamics of quantum Fisher information shows oscillatory and rising behaviors.To estimate the temperature of the thermal reservoir,the one-qubit probe with the superposition initial state is more favorable than the two-qubit probe with the entangled initial state.When the squeezing strength of the squeezed vacuum reservoir is estimated,we find that the estimation precision is significantly improved by utilizing the two-qubit probe with the maximal entangled initial state.Our work provides a potential application in the open quantum system and quantum information processing.
基金supported by the National Natural Science Foundation of China (Grants No.12275062,No.11935012,and No.61871162)。
文摘Simultaneously optimizing the estimation of the centroid and separation of two incoherent optical point sources is constrained by a tradeoff relation determined by an incompatibility coefficient.At the Rayleigh distance,the incompatibility coefficient vanishes and thus the tradeoff relation no longer restricts the simultaneous optimization of measurement for a joint estimation.We construct such a joint optimal measurement by an elaborated analysis on the operator algebra of the symmetric logarithmic derivative.Our work not only confirms the existence of a joint optimal measurement for this specific imaging model,but also gives a promising method to characterize the condition on measurement compatibility for general multiparameter estimation problems.
