3D micro-printed hybrid photonic structure for single-fiber Optical Tweezers

Optical tweezers (OT) are non-destructive, contactless tools that use light to trap and manipulate microscopic objects. They have applications in diverse fields, particularly in biomedicine and physics [1] . Due to their unique applications and the ability to analyze sub-micron biological systems, the Nobel prize for Physics in 2018 was awarded to Arthur Ashkin, the inventor of OT. Conventional single-beam OT setups require the focusing of a laser beam with a high-Numerical Aperture (NA) objective. However, these setups are bulky and restrict the trapping capabilities to table-top arrangements. The miniaturization of OT to be implemented with a single optical fiber is vital as it opens up new possibilities such as trapping in turbid media or in-vivo. Several groups demonstrated single-fiber OT but the proposed approaches use non-standard fibers and grant only limited design flexibility in controlling the optical trap geometry [2] .