We report an enhanced sensitivity for detecting linear perturbations near hybrid (doubly degenerated) exceptional-diabolic (HED) singular points in a four mode bosonic system. The sensitivity enhancement is attributed to a singular response function, with the pole order determining the scaling of estimation error. At HED singular points, the error scaling exhibits a twofold improvement over non-HED singular points. The ultimate bound on estimation error is derived via quantum Fisher information, with heterodyne detection identified as the measurement achieving this optimal scaling.
Cite
@article{arxiv.2502.03780,
title = {Enhanced quantum sensing with hybrid exceptional-diabolic singularities},
author = {Javid Naikoo and Ravindra W. Chhajlany and Adam Miranowicz},
journal= {arXiv preprint arXiv:2502.03780},
year = {2025}
}
Comments
The paper consists of 13 pages with 3 captioned figures and appendices