METHOD FOR PASSIVE ATOMIC FREQUENCY STANDARD BASED ON COHERENT POPULATION TRAPPING USING INJECTION-LOCKED LASERS

摘要

A frequency standard obtaining method within an atomic clock based on CPT(Coherent Population Trapping) by using an injection-locked laser is provided to design a CPT resonance-based frequency standard including CPT signals with improved contrast by removing a carrier and sidebands that are not contributed to CPT. Two coherent lasers are formed by an injection lock structure. In the injection lock structure, an ECDL(External Cavity Diode Laser) operated in a single mode is used as a main laser(L1) and a Fabry-Perot laser diode operated in a single mode is used as a sub laser(L2). The coherent lasers irradiated from the main and sub lasers and operated in a single mode, respectively progress in the same direction while passing through rubidium vapor cells(4,5). Therefore, the CPT spectrum is stabilized within an atomic clock by using the rubidium vapor cell, in order to provide the CPT-based frequency standard.