6533b838fe1ef96bd12a4d4b

RESEARCH PRODUCT

Trapping and manipulation of colloidal objects using silicon photonic structures integrated into optofluidic chips

subject

description

Near-field optical forces arise from evanescent electromagnetic fields, such as in the near-field of photonic waveguides and nanocavities where light is highly confined. These contactless forces can be advantageously used to trap and manipulate micro- and nano-objects in solution. This thesis aims at studying these intriguing interactions and investigating their potential applications. The first chapter is an introduction to the fields of colloidal systems and optical trapping, more especially using near-field optical forces. The second chapter presents the experimental setup and the process used to fabricate optofluidic chips with microfluidic channels. The trapping potential experienced by 2 µm, 1 µm, and 500 nm microbeads at the surface of a photonic nanocavity is studied in the third chapter. Our results lead to the concept of optofluidic near-field optical microscopy. In the fourth chapter, we study the dynamics and the manipulation of trapped microbeads clusters in fluidic flows. The last chapter focuses on the trapping and the manipulation of microbeads at the surface of waveguides using copropagating modes.