FIG. 9.

Relationship between the concentration time t_c interpolated from the data in Fig. 8 as a function of the particle dimension $1/{\varphi }_p^2$ scaling for a fixed input power (100 mW), under different amplitude modulations condition: f_m = 0 (without modulation) (◇), f_m = 1 kHz (×), f_m = 5 kHz (●), and f_m = 15 kHz (△). Error bars indicate a ±2 standard deviation (95% confidence level) from the mean.