The study of quantum systems interacting with their environment helps in characterizing the behavior of the dynamics of the system. This is useful in many application of quantum mechanics and has lead to the field of open quantum systems. In my talk, based on Phys. Rev. Lett. 131, 220801 (2023), I will delve into the cutting- edge realm of quantum sensing, focusing on the utilization of dynamical singularities to achieve unbounded sensitivity in the error in estimating unknown parameters. Quantum systems governed by non-Hermitian generators offer a unique avenue for exploring dynamical properties, including phenomena such as exceptional points and the preservation of parity- time symmetry. Leveraging these properties, we investigate the potential for achieving unbounded sensitivity in sensing linear perturbations away from singular points. By integrating the multiparameter estimation theory of Gaussian quantum systems with the study of singular-matrix perturbations, we introduce a novel framework for analyzing the ultimate limits of precision attainable by singularity-tuned sensors. Our exploration aims to identify the conditions under which sensitivity diverges and at what rate, shedding light on the fundamental capabilities of these quantum sensors. Moreover, we highlight the significance of accounting for nuisance parameters in the analysis, as their presence may significantly impact the scaling of error with the estimated parameter. Through this comprehensive investigation, we aim to contribute to the advance- ment of quantum sensing technology and pave the way for future developments in precision measurement and quantum information processing. This talk will not only showcase the theoretical underpinnings of our research but also demonstrate its practical implications for the field of quantum sensing and beyond.

Meeting ID: 914 4094 2394
Passcode: 626590