Quantum Metrology Under Fast Entanglement Generation with Lipkin-Meshkov-Glick (LMG) Model

Zeyang Li | Simone Colombo | Chi Shu | Edwin Pedrozo | Enrique Mendez | Boris Braverman | Vladan Vuletic

Many of the state-of-the-art quantum sensors are limited by quantum shot noise. By using quantum entanglement, one can go beyond this limit. Especially when a quantum system undergoes chaotic or unstable evolutions, the quantum state’s sensitivity exponentially increases in time. However, such regimes have not yet been thoroughly investigated, partially due to the lack of coherence and controllability of these strongly interacting systems. In this work, we experimentally demonstrate the implementation of the Lipkin-Meshkov-Glick (LMG) model in a cavity QED system that features an unstable evolution. Also, we show the control of such quantum states and directly demonstrate the connection between the exponential behavior of the Fidelity Out-of-time-ordered correlators (FOTOC) and the quantum metrological gain.

Funding Sources: NSF | DARPA | ONR | NSF CUA | NSF QLCI-CI QSEnSE