Stabilization of Rydberg dissipative time crystals using a scanning Fabry–Pérot interferometer transfer lock

Abstract

Stabilization of laser frequencies is critical for sensitive Rydberg measurements, including in applications such as dissipative time-crystal (DTC) dynamics, yet conventional approaches often require complex or costly hardware. We demonstrate a compact, low-cost stabilization method using a scanning Fabry–Pérot interferometer (SFPI) to transfer lock a 960 nm coupler laser to an 852 nm Cs reference laser. The lock suppresses coupler multi-MHz free-running drift and improves the Allan deviation by up to an order of magnitude, reaching <75 kHz at τ ∼ 66 s. Applied to DTC oscillations using a Rb 2-photon D2 transition, the second harmonic generated at 480 nm (from 960 nm lock) reduces DTC frequency drift from >20 kHz to a few kHz and lowers instability by more than an order of magnitude with a minimum Allan deviation of 0.2 kHz at τ < 10 s. These results establish SFPI-based transfer locking as a practical and accurate approach for scalable multi-laser Rydberg experiments that require long-term stability in a compact and low-cost system.