Brook Feyissa | Searcharxiv

arXiv2026

Stabilization of Rydberg Dissipative Time Crystals Using a Scanning Fabry Perot Interferometer Transfer Lock

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 Perot interferometer (SFPI) to transfer lock a 960nm coupler laser to an 852nm probe. The lock suppresses coupler multi MHz free running drift and improves the Allan deviation by up to an order of magnitude, reaching <75kHz at 66s. Applied to DTC oscillations using a Rb 2 photon D2 transition, the second harmonic generated 480nm (from 960nm lock) reduces DTC frequency drift from >20kHz to a few kHz and lowers instability by more than an order of magnitude with a minimum Allan deviation of 0.2kHz at <10s. These results establish SFPI-based transfer locking as a practical and accurate approach for scalable multi laser Rydberg experiments requiring long-term stability in a compact and low cost system.

physics.atom-ph↗

arXiv2024

Remote sensing of soil moisture using Rydberg atoms and satellite signals of opportunity

Spaceborne radar remote sensing of the earth system is essential to study natural and man-made changes in the ecosystem, water and energy cycles, weather and air quality, sea level, and surface dynamics. A major challenge with current approaches is the lack of broad spectrum tunability due to narrow band microwave electronics, that limit systems to specific science variable retrievals. This results in a significant limitation in studying dynamic coupled earth system processes such as surface and subsurface hydrology, where broad spectrum radar remote sensing is needed to sense multiple variables simultaneously. Rydberg atomic sensors are highly sensitive broad-spectrum quantum detectors that can be dynamically tuned to cover micro-to-millimeter waves with no requirement for band-specific electronics. Rydberg atomic sensors can use existing transmitted signals such as navigation and communication satellites to enable remote sensing. We demonstrate remote sensing of soil moisture, an important earth system variable, via ground-based radar reflectometry with Rydberg atomic systems. To do this, we sensitize the atoms to XM satellite radio signals and use signal correlations to demonstrate use of these satellite signals for remote sensing of soil moisture. Our approach provides a step towards satellite-based broad-spectrum Rydberg atomic remote sensing.

physics.app-ph↗