Our group alumni, Dr. Kimin Park from Palacky University, will be giving a seminar

  Speaker: Dr. Kimin Park (Department of Optics, Palacky University, Olomouc, Czech Republic)

Title: Quantum Sensing with Unbalanced Cat States: A Practical Pathway Beyond the Gaussian Bound

Abstract
Quantum metrology aims to enhance measurement precision beyond classical limits. A critical milestone in this field is to surpass the fundamental Gaussian bound. However, the non-Gaussian states required to achieve this are often fragile and experimentally demanding to create. This talk presents a practical and robust pathway to overcome this challenge using asymmetric superpositions of coherent states (SCS), or "unbalanced cat states." We explain how asymmetry is the key resource: for a fixed energy budget, a larger vacuum component allows for maximizing the state's phase-space separation, which dramatically boosts measurement precision. Our protocol, implemented on a circuit QED platform, is experimentally feasible and efficient. We demonstrate a 7.5 dB metrological gain over the classical limit, confirming the quantum advantage. This work establishes asymmetric SCS as a high-performance and scalable resource for next-generation quantum sensors.

[1] Park et al, arXiv:2508.13046
[2] Pan et al, PRX Quantum 6, 010304 (2025)