Multiparameter Estimation Perspective on Non-Hermitian Singularity-Enhanced Sensing
Javid Naikoo, Ravindra W. Chhajlany and Jan Kołodyński
PRL 131, 220801 (2023)
Describing the evolution of quantum systems by means of non-Hermitian generators opens a new avenue to explore the dynamical properties naturally emerging in such a picture, e.g. operation at the so-called exceptional points, preservation of parity-time symmetry, or capitalizing on the singular behavior of the dynamics.
In this Letter, we focus on the possibility of achieving unbounded sensitivity when using the system to sense linear perturbations away from a singular point. By combining multiparameter estimation theory of Gaussian quantum systems with the one of singular-matrix perturbations, we introduce the necessary tools to study the ultimate limits on the precision attained by such singularity-tuned sensors. We identify under what conditions and at what rate can the resulting sensitivity indeed diverge, in order to show that nuisance parameters should be generally included in the analysis, as their presence may alter the scaling of the error with the estimated parameter.
About the qGAP meeting series
Welcome to qGAP, our seminar series on Quantum Physics and Quantum Technology.
The series of seminars/lectures are meant to cover broadly activities at UiO and elsewhere related to quantum physics and technologies, mainly from a theoretical perspective, though we also welcome experimental talks.
We aim at having regular seminars, discussions of recent articles, presentations by master and PhD students and more. We aim for this series to be a combination of research talks and journal clubs.
Educational topics are also most welcome.
Please feel free to suggest speakers, yourself included!
Get in touch with Gunnar Lange to suggest a speaker or if you would like to be included in the mailing list.
All are welcome!
Upcoming:
21. Februar - Viktor Svensson (UiO Fysikk)
27. Februar - Sølve Selstø (OsloMet)
28. March - Franz Georg Fuchs (Sintef/UiO Matematikk)
4. April - Alexander Müller-Hermes (UiO Matematikk)
11. April - Shaukat Ali (Simula)
25. April Kristian Wold (OsloMet) i qGap