A compact coherent population trapping clock with a short-term fractional frequency stability of 4.2 x 10-13 τ-1/2

Abstract

Based on the constructive polarization modulation coherent population trapping, we demonstrated a cw mode CPT clock with a short-term fractional frequency stability at the level of 4.2 x 10-13 ?-1/2 up to the averaging time of 100 seconds. This high performance and compact CPT atomic clock would lead more applications which concern on both the frequency stability and the compactness.