Fig. 2: Characterization of bubble generation.
a (top) Bubble radius linearly increases with laser intensity. (bottom) bubble volume vs laser intensity. Minimum required laser intensity as a function of b AC frequency, c DC bias, and d Na2SO4 electrolyte concentration. Unless stated otherwise, conditions used in characterization: 0.1 M Na2SO4 solution, −5 V DC/12 Vpp at 1.5 kHz AC E-field applied for ~225 ms, and 500 μm PDMS well. e Schematic of the overall setup and corresponding equivalent circuit. f Optimization of the limit of light intensity for bubble generation. Conditions: (Black) 0.5 M Na2SO4, −5 V, 12 Vpp at 1.5 kHz, 100 ms, PDMS 500 µm. (Orange) PBS solution, −9 V, 2Vpp at 250 Hz, 200 ms, PDMS 100 µm. (Green) 0.75 M Na2SO4, −5 V, 10 Vpp at 1.5 kHz, PMDS 100 µm. (Blue) 1.5 M Na2SO4 with CTAC and H2O2, −12 V DC pulse with 50% duty cycle, 150 ms, PDMS 257 µm. Error bars: standard deviation (s.d.). Source data are provided as a Source Data file.
