Progress Toward a Compact Two-Photon Rb Clock with Long-Term Stability Below 10^-15

Abstract

Progress on the development of a compact twophoton Rb clock designed for timekeeping applications is presented. Current short-term and long-term limitations of the technology are discussed. Continuous operation during 4 months of an integrated prototype at the Swiss national metrology institute (METAS), measured against UTCr, is reported.