Speaker: Declan Armstrong 
Affiliation: University of Queensland

Abstract

Two-Photon-Photopolymerisation (2PP) provides a means to produce versatile 3D micro-structures for optical trapping and cell study experiments with sub-diffraction-limited resolution. In this talk, I demonstrate how a holographic optical trapping apparatus can be modified to rapidly design, fabricate, and utilise 3D structures in-house with commonplace optical components. Fabrication using dozens of simultaneous, independent polymerising foci is achieved with the aid of an in-situ (within the sample) aberration correction algorithm, capable of correcting arbitrary beam distortions imposed by any number of optical elements. This robust algorithm is shown to be capable to focusing light even through scattering media using phase modulation to maximise interference between orthogonal modes on a Spatial Light Modulator (SLM). Finally, I demonstrate how micro-structures can be used to test simple models of collective motion using geometric confinement of Escherichia coli (E. coli) bacteria.

About Physics Seminars

The weekly Physics Seminar series focuses on a broad range of physics research within SMP, along with frequent presentations from visiting researchers. Seminars are usually scheduled for 1.00pm on Tuesdays.

The talks are typically more specialised than a colloquium but are often attended by staff and PhD students across a broad range of areas. Speakers are thus encouraged to include introductory material in the talks.

All SMP researchers and HDR students are encouraged to speak. Please email Lewis Williamson to register your interest.

The seminars are open so there is no need to register your attendance.

Venue

Physics Annexe (6)
Room: 407 (and via Zoom:
https://uqz.zoom.us/j/94116861984)