Bosonic Pair Production and Squeezing for Optical Phase Measurements in Long-Lived Dipoles Coupled to a Cavity

We propose to simulate bosonic pair creation using large arrays of long-lived dipoles with multilevel internal structure coupled to an undriven optical cavity. Entanglement between the atoms, generated by the exchange of virtual photons through a common cavity mode, grows exponentially fast and is described by two-mode squeezing of effective bosonic quadratures. The mapping between an effective bosonic model and the natural spin description of the dipoles allows us to realize the analog of optical homodyne measurements via straightforward global rotations and population measurements of the electronic states, and we propose to exploit this for quantum-enhanced sensing of an optical phase (common and differential between two ensembles). We discuss a specific implementation based on Sr atoms and show that our sensing protocol is robust to sources of decoherence intrinsic to cavity platforms. Our proposal can open unique opportunities for next-generation optical atomic clocks.

Automated summary

We propose a method to simulate the creation of bosonic pairs using long-lived dipoles with multilevel structures coupled to an optical cavity. Entanglement between the atoms is achieved through the exchange of virtual photons, leading to exponential growth and described by two-mode squeezing. By mapping the effective bosonic model to the natural spin description, we can realize optical homodyne measurements and utilize this for quantum-enhanced sensing of an optical phase.