To extend beyond the limited field of view associated with optical tweezers, we implement a new geometry for lensless optical trapping ("LOT"). A Ronchi ruling is imaged at a sample interface beyond the critical angle for total internal reflection imposing local structure upon the optical fields. Due to the resulting transverse optical gradients, more than one thousand microparticles spanning 1 mm2 were organized into microchannels that are entirely optical in origin. A generalized approach is presented, allowing for either guiding or stable trapping, as a function of the relative intensity of the counterpropagating surface waves.
Bibliographical noteFunding Information:
This work was supported by the European Science Foundation, the Leverhulme Trust and the U.K. Engineering and Physical Sciences Research Council. G.C.S. is also supported by an award from the Research Corporation and by the National Science Foundation through Grant No. DMR-0216631.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy (miscellaneous)