- Letter
Three-photon Rydberg-atom-based radio-frequency sensing scheme with narrow linewidth
Phys. Rev. Applied 20, L061004 – Published 21 December, 2023
DOI: https://doi.org/10.1103/PhysRevApplied.20.L061004
Abstract
We demonstrate Rydberg atom-based radio-frequency sensing with a colinear three-photon scheme in a room-temperature cesium vapor cell that minimizes residual Doppler broadening of the probe-laser absorption feature. A sub-200-kHz spectral linewidth is observed and extends the self-calibrated Autler-Townes sensing regime to weaker fields by a factor of 18 compared to the theoretical limit of the most commonly used two-photon scheme. The sensitivity of the method to microsecond pulses is shown to be sufficient to detect radio-frequency Rabi frequencies of 2π × 0.44 MHz using a 480-kHz bandwidth at 108.9 GHz, demonstrating the ability to sense time-dependent signals suitable for radar and communications.
