Shane, Janelle CMazilu, MichaelLee, Woei MingDholakia, Kishan2016-05-302016-05-301094-4087http://hdl.handle.net/1885/101765We investigate the effects of pulse duration on optical trapping with high repetition rate ultrashort pulsed lasers, through Lorentz-Mie theory, numerical simulation, and experiment. Optical trapping experiments use a 12 femtosecond duration infrared pulsed laser, with the trapping microscope's temporal dispersive effects measured and corrected using the Multiphoton Intrapulse Interference Phase Scan method. We apply pulse shaping to reproducibly stretch pulse duration by 1.5 orders of magnitude and find no material-independent effects of pulse temporal profile on optical trapping of 780nm silica particles, in agreement with our theory and simulation. Using pulse shaping, we control two-photon fluorescence in trapped fluorescent particles, opening the door to other coherent control applications with trapped particles.The authors are grateful to the UK Engineering and Physical Sciences Research Council (EPSRC) for funding. MM acknowledges support from Scottish Enterprise. JS was supported in part by a USA National Science Foundation Graduate Research Fellowship.15 pages© 2010 Optical Society of America. This is an open access journal https://www.osapublishing.org/oe/journal/oe/about.cfm (Publisher journal website as of 30/5/2016).algorithmselectromagnetic fieldsfourier analysislasersmaterials testingmicroscopy, fluorescence, multiphotonmodels, statisticaloptical tweezersparticle sizephotonssilicon dioxidetime factorsoptics and photonics2010-03-2910.1364/OE.18.007554