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ta t a en ie, antu, Tai vemb zed s ot co.1 dB he tw ngth dB 200 type I x nonlinear crystal have been used to gener-ate amplitude squeezing of infrared and green light minimal variances of two output modes: June 15, 2005 / Vol. 30, No. 12 / OPTICS LETTERS 1491simultaneously.3,5,16 In this Letter we report the gen-eration of a vacuum-squeezed state of 3.2 ± 0.1 dB and a bright amplitude-squeezed state of 1.3 ± 0.2 dB simultaneously from a simple doubly resonant second-harmonic generator (doubler) con-sisting of a type II crystal with a pump power of 8 mW. As much as 5.0±0.2 dB of maximum vacuum squeezing was observed at a pump power of 19 mW. The theoretical calculations in Refs. 17 and 18 show that, below the oscillation threshold19 of mode as in the doubler, a vacuum-squeezed mode with an average intensity close to zero and an amplitude-squeezed mode ap with nonzero average intensity can be obtained. The variances of the quantum fluctua-tions for mode ap and mode as, VdXp, and VdYs, respec-tively, are1