Fig. 3: Strong artificial radiation pressure.
From: Single-photon quantum regime of artificial radiation pressure on a surface acoustic wave resonator
a Normalized output power of the MW signal coherently up-converted from the SAW excitations as a function of the detuning of the SAW drive frequency (dots). Three datasets are for different drive powers represented by the average number, nd, of drive photons in the MW resonator. Dashed curves are the results of fittings with a sum of three Lorentzians in the complex plane. The left-most peak is from the fundamental transverse mode of the SAW resonator, while the two other peaks are due to higher-index transverse modes. b Cooperativity C as a function of the drive photon number nd. White area corresponds to the single-photon quantum regime, i.e., C0 > 1. Cyan dots are the experimental data at Φ = 0.445Φ0 = Φα=0. Purple dots are taken at Φ = 0.264Φ0, where α ≠ 0 and the saturation takes place at lower power. Black dashed line is the linear fit for the cyan dots in the low-power region. Inset shows an enlarged view near the origin. Error bars represent standard errors.
