Seminar by S. Felicetti Friday October 22 at 4 pm in Conversi

We are pleased to announce a seminar by  Dr. Simone Felicetti  from the Institute for Photonics and Nanostructures of CNR, to be held on October Friday 22nd in Aula Conversi at 4 pm.

Title: “Critical parametric quantum sensing”

Quantum critical systems in proximity of phase transitions exhibit a divergent susceptibility, suggesting that an arbitrarily-high precision may be achieved when they are used as probes to estimate a physical parameter. However, such an improvement in sensitivity is counterbalanced by the critical slowing down, which implies an inevitable growth of the protocol duration time [1]. Here, we present sensing protocols based on phase transitions observable in a broad class of quantum optical systems. We show that, in spite of the critical slowing down, critical quantum optical probes can achieve quantum advantage in sensing applications [2]. By going beyond the asymptotic regime of parameters [3], we show that Heisenberg-limited precision can be achieved with current quantum technologies. Finally, we propose specific applications for quantum magnetometry and for superconducting-qubit readout.

[1] M. M. Rams, P. Sierant, O. Dutta, P. Horodecki, and J. Zakrzewski, Phys. Rev. X 8, 021022 (2018).
[2] L. Garbe, M. Bina, A. Keller, M. Paris, and S. Felicetti, 
 Phys. Rev. Lett. 124, 120504 (2020).
[3] R. Di Candia, F. Minganti, K. V. Petrovnin, G. S. Paraoanu, S.Felicetti, 
 arXiv:2107.04503 (2021).
[4] P. Krantz, A. Bengtsson, M. Simoen, S. Gustavsson, V. Shumeiko, W. D. Oliver, C. M. Wilson, P. Delsing & J. Bylander, Nat. Comm. 7, 11417 (2016).

Sketch of the steady state Wigner function as the system goes from the normal to the symmetry breaking phase.

Sketch of the superconducting qubit read-out scheme implemented in [4].




Talk’s slides can be downloaded here