Retrieving Ideal Precision in Noisy Quantum Optical Metrology

Abstract

Quantum metrology employs quantum effects to attain a measurement precision surpassing the limit achievable in classical physics. However, it was previously found that the precision returns the shot-noise limit (SNL) from the ideal Zeno limit (ZL) due to the photon loss in quantum metrology based on Mech-Zehnder interferometer. Here, we find that not only the SNL can be beaten, but also the ZL can be asymptotically recovered in long-encoding-time condition when the photon dissipation is exactly studied in its inherent non-Markovian manner. Our analysis reveals that it is due to the formation of a bound state of the photonic system and its dissipative noise. Highlighting the microscopic mechanism of the dissipative noise on the quantum optical metrology, our result supplies a guideline to realize the ultrasensitive measurement in practice by forming the bound state in the setting of reservoir engineering.Introduction.-Pursuing high-precision measurement to physical quantities, metrology plays a significant role in advancing the innovation of science and technology. Restricted by the unavoidable errors, the metrology precision realized in classical physics is strongly bounded by the shot-noise limit (SNL) N −1/2 with N being the number of resource employed in the measurements. It was found that the SNL can be beaten by taking advantage of the quantum effects such as squeezing [1-3] and entanglement [4][5][6]. This inspires the birth of a newly emerged field, quantum metrology [7][8][9]. Many fascinating applications of quantum metrology have been proposed. The quantum effects of light can offer enhanced imaging resolution [10][11][12] in biological monitoring [13][14][15] and in optical lithography [16], and improved sensitivity in gravitational wave detection [17] and in radar [18]. The quantum characters of atoms or spins can provide an enhanced precision in sensing weak magnetic field [19][20][21][22][23][24] and ultimate accuracy for clocks [25][26][27].

Quantum control in open and periodically driven systems

“…It has been reported that such a bound state has profound impacts on many quantum protocols and nonequilibrium physics, e.g. entanglement preservation [28][29][30], noncanonical thermalization [31], quantum speed limit [32], and quantum metrology [33][34][35]. The results give us an insightful guideline to control decoherence via forming the bound state by quantum reservoir engineering [36,37].…”

Quantum metrology enhanced by coherence-induced driving in a cavity-QED setup

“…To deal with this issue, dynamical decoupling 5,25 , feedback control [26][27][28] and many other approaches have been developed. Moreover, non-Markovian effect is also shown to be effective to maintain entanglement-induced high measurement precision 29,30 . Most of the above works focus on how to prepare or protect entangled states for quantum metrology.…”

Enhancing Parameter Estimation Precision in a Dissipative Environment with Two‐Photon Driving

“…[ 34 ] and Bai et al. [ 35 ] revealed that the Heisenberg limit and the ideal Zeno limit could be recovered in a long‐encoding‐time condition, which is attributed to the non‐Markovian effect and the formation of a bound state between the quantum probe and its dissipative environment. However, a unique coupling spectral density is required to form the bound state.…”