Optical trapping using ultrashort 12.9fs pulses

We demonstrate stable three-dimensional optical trapping of 780nm silica particles using a dispersion-compensated 12.9fs infrared pulsed laser and a trapping microscope system with 1.40NA objective. To achieve these pulse durations we use the Multiphoton Intrapulse Inteference Phase Scan (MIIPS) method to compensate for the significant temporal dispersion introduced by the trapping system. We demonstrate orders of magnitude reduction in pulse duration at the sample, and a dramatic increase in the efficiency of multiphoton excitation at the sample. The use of dispersion-compensated ultrashort pulses will therefore be a valuable tool for enhancing non-linear processes in optically trapped particles. In addition, ultrashort pulses can allow the use of pulse shaping to control these nonlinear processes, yielding the possibility of advanced applications using coherent control of trapped particles.