Squeezing at 946nm with periodically-poled KTiOPO₄

We report generation of squeezed vacuum in sideband modes of continuous-wave light at 946 nm using a periodically poled KTiOPO_4 crystal in an optical parametric oscillator. At the pump power of 250 mW, we observe the squeezing level of -5.6+/-0.1 dB and the anti-squeezing level of +12.7+/-0.1 dB. The pump power dependence of the observed squeezing/anti-squeezing levels agrees with the theoretically calculated values when the phase fluctuation of locking is taken into account.