| 초록 |
The multibody capillary interactions of Janus microspheres at an oil-water interface are measured via optical laser tweezers based on both the active and passive methods. Two particles are held by stationary traps, and a translational particle approaches the stationary particles. The multibody interactions caused by capillarities are then quantified and visualized as functions of the interparticle separations. In addition, the obtained forces measured by the active method are compared with those by the passive measurement method. In the later case, optically trapped particles arranged in a straight line are released from the optical traps, and the drift velocity while they spontaneously approach each other is converted to the Stokes’ drag force. The resulting power-law scaling exponent of the interaction force consistently demonstrates that the capillary force is govern by the quadrupolar capillary attraction. |
