Demonstration of trapping, motion control, sensing and fluorescence detection of polystyrene beads in a multi-fiber optical trap

We demonstrate a multi-functional optical trap capable of trapping, motion control, position sensing and fluorescence detection of chemically treated polystyrene beads, using off-the-shelve optical components. It consists of two collinearly aligned single-mode fibers separated by a spacing of 130-170 mu m for trapping, another single-mode fiber for probing/pumping and a fourth multi-mode fiber for optical detection. The fibers are mounted either on V-grooved Si or PDMS platforms fabricated using microfabrication and molding techniques, respectively. The result represents an important milestone towards a functional integrated trapping platform. (C) 2005 Optical Society of America.