Physics Colloquium: “Manipulating Colloidal Particles with Light: Simulations and Experiments”

The Syracuse University Department of Physics is pleased to welcome Dr. Jerome Fung, Assistant Professor of Physics at Ithaca College, Ithaca, NY.

“Manipulating Colloidal Particles with Light: Simulations and Experiments”

One of the most practical applications of the ability of light to exert mechanical forces is optical tweezers, in which a focused laser beam can exert forces on and trap particles ranging in size from a few nanometers to a few micrometers. Yet, predicting the behavior of micrometer-sized particles in optical tweezers, and in complex beams more generally, is more challenging than one might expect, particularly when the particles lack symmetry. In this talk, I will discuss recent work in which we have used tools for computing how wavelength-sized particles scatter light to perform Brownian dynamics simulations of particles in Laguerre-Gaussian beams that account for optical, hydrodynamic, and thermal forces on the particles. The simulations reveal new ways in which light – in both optical tweezer and optical vortex beams – can drive the motion of colloidal particles in fluids. I will also discuss our ongoing experimental efforts to use optical tweezers to measure the interactions between soft polymer particles that could be useful for studying the glass transition.

Jerome Fung is currently Assistant Professor of Physics at Ithaca College, where he teaches courses across the curriculum and mentors undergraduates in optics and soft condensed matter research. Before coming to Ithaca College, Jerome was Lecturer in Physics at Wellesley College. Prior to that, he performed postdoctoral research on colloidal membranes formed from filamentous bacteriophages at Brandeis University. Jerome earned his PhD in Physics at Harvard University, studying holographic microscopy and colloidal suspensions. Jerome completed his undergraduate studies at Swarthmore College, where his first exposure to research was in experimental plasma physics.