Diode-pumped Nd:FAP laser at 1126 μm: a possible local oscillator for a Hg^+ optical frequency standard

We report the efficient operation of a continuous-wave, single-frequency, diode-pumped Nd:FAP laser at 1.126 mum. When frequency quadrupled, such a laser might be used as a local oscillator for an optical frequency standard based on the single-photon (2)S(1/2)-(2)D(5/2) electric quadrupole transition of a trapped and laser-cooled (199)Hg(+) ion. Since the frequencies of the atomic transition and the laser are harmonically related, this scheme helps to simplify the measurement of the S-D clock transition frequency by a phase-coherent chain to the cesium primary frequency standard.