To help minimize the spread of COVID-19, some events are being offered virtually, and in-person events have additional safety requirements.
If you have questions about what’s open around campus, please check out this regularly updated guide.
Abstract: The ability to sculpt light fields using spatial light modulators (SLM) or Digital Micromirror Devices (DMD) has given us tools of choice for the production of configurable and flexible confining potentials at the nano and micron-scale. We categorise the techniques used to create sculpted light to those based on time averaged methods and those utilising spatial light modulators in either Fourier plane or direct imaging plane. A rapid angular modulation of Gaussian beam with a two-axis acousto-optic modulator, AOM, can be used as highly configurable time-averaged traps. This type of modulation has found applications in holographic tweezers and ring traps for ultra-cold atoms. SLMs can be used as a way of producing extremely versatile structured light. SLMs in Fourier plane which control the phase and /or amplitude of an input Gaussian beam, with the pattern representing the spatial Fourier transform of the desired amplitude pattern. The optical system then focuses this sculpted light pattern to the plane containing the system of interests, performing a Fourier transform and recovering the desired pattern. Yet another way for production of dynamical, fast and flexible structured light fields is using digital micromirror devices (DMD), which is based on direct imaging of amplitude patterns. DMD can configure the amplitude of an input beam either in the Fourier plane or in a direct imaging configuration. Sculptured light produced using these methods promises high flexibility and an opportunity for trapping and driving systems ranging from studies of quantum thermodynamics using ultra cold atoms to trapping and manipulating nano and micron-size objects or even using these objects inside a biological cell.
Biography: Halina Rubinsztein-Dunlop is Professor of Physics in the School of Mathematics and Physics at the University of Queensland. She was educated at the University of Gothenburg and Chalmers University of Technology, Gothenburg in Sweden. She is a Director of ARC CoE for Engineered Quantum Systems Translational Research Laboratory and was for 9 years Head of School of Mathematics and Physics. At the University of Queensland Halina leads a large research groups in experimental quantum atom optics, laser micromanipulation and biophotonics. She also leads a program in the ARC Centre of Excellence in Engineered Quantum Systems. Halina has been awarded Australian Institute of Physics International Woman in Physics, Lecture Tour Medal and University of Queensland Award for Excellence in Research Higher Degree Supervision. Halina is a Fellow of Australian Academy of Science, a Fellow of SPIE and of OSA. Halina was awarded Officer in the General Division (AO) of the Order of Australia for distinguished service to laser physics and nano-optics as a researcher, mentor and academic, to the promotion of educational programs, and to women in science in June 2018. She was also awarded Australian Optical Society W.H. (Beattie) Steel Medal, 2018 and 2018 Eureka Prizes in UNSW Eureka Prize for Excellence in Interdisciplinary Scientific Research (Optical Physics in Neuroscience), 2018. In 2019 she was awarded Lise Meitner Distinguished Lecture Tour 2019 Germany and Austria. In 2021Halina was awarded the OSA 2021 C.E.K. Mees Medal. Rubinsztein-Dunlop’s group has published over 295 papers that have received over 10272 citations in the world’s leading scientific journals. Halina is also actively involved in popularisation and promotion of science.