Extended Data Fig. 3: Thermal occupation and heating.
a, Thermal phonon occupation of the mechanical mode versus repetition time of the optical pump pulse. As explained in Methods, the thermal occupation is calculated from sideband asymmetry between the blue- and red-detuned pump pulse. The error bars correspond to the standard deviation over 23 sets of sideband asymmetry measurements with data points representing the mean values. b, Time-domain heating of the optical pulse at 6 μs repetition, measured with microwave readout of the mechanical mode. Variance of the microwave noise is measured and calibrated to thermal phonon number with optical sideband asymmetry. Dashed red line is the exponential fit of the decaying tail of the thermal phonon occupation.
