Near-field optical forces arise from evanescent electromagnetic fields and can be advantageously used for on-chip optical trapping. In this work, we investigate how evanescent fields at the surface of photonic cavities can efficiently trap micro-objects such as polystyrene particles and bacteria. We study first the influence of trapped particle’s size on the trapping potential and introduce an original optofluidic near-field optical microscopy technique. Then we analyze the rotational motion of trapped clusters of microparticles and investigate their possible use as microfluidic micro-tools such as integrated micro-flow vane. Eventually, we demonstrate efficient on-chip optical trapping of various kinds of bacteria.

Date Published: 18 April 2017
PDF: 4 pages
Proc. SPIE 10252, Optical Manipulation Conference, 1025212 (18 April 2017); doi: 10.1117/12.2275013

Published in SPIE Proceedings Vol. 10252:
Optical Manipulation Conference
Takashige Omatsu, Editor(s)