非線形共鳴光トラッピング

抄録

The principle of optical trapping is based on the interaction between optical electric fields and induced polarizations (gradient force). Here we describe a novel trapping phenomenon that arises from nonlinear polarization using ultrashort near-infrared laser pulses. A stable trap site is split into two equivalent positions, in contrast to conventional (linear) optical trapping where the trap site is at the center of the focus. The trapping behavior with ultrashort pulses is successfully interpreted in terms of the nonlinear polarization induced on the trapped particles. Nonlinear optical trapping might greatly expand the potential of optical trapping.