Reconfigurable 3-dimensional optical route formed by fiber-optic pseudo-Bessel beam arrays

We present a novel implementation of Fourier optics along a single strand of hybrid optical fiber in a monolithic manner that can generate a highly efficient pseudo-Bessel beam. The incident fundamental mode of an optical fiber is adiabatically transformed to multiple ring modes by interference within a coreless silica fiber, which serves as a micro annulus apertures. A micro polymer lens was formed at the end face to complete the Fourier-transform providing a pseudo-Bessel beam at the output. Efficient multiple particle trapping experiments for both polystyrene beads were realized over 1 mm distance along the pseudo-Bessel beam. Furthermore all-optical transport of the trapped particles along a three dimensional optical route was demonstrated by spatially multiplexing pseudo-Bessel beams via multi mode interference (MMI) type Bessel beam generators. 1×3 pseudo-Bessel beam multiplexer was installed in the water based solution with 10mm(micro meter?) polystyrene beads. After a polystyrene particle was trapped by pseudo-Bessel beam, the initial acceleration was observed as 150μm/s². The final velocity of the trapped particle maintained about 300μm/s with 40μm/s undulation due to pseudo-Bessel beam crossing points. The spatial multiplexing of fiber optic pseudo- Bessel beam arrays could make a new building block to realize reconfigurable all-optical transportation of particles.