Seminar: Opportunities for X-Ray Super-Resolution Sensing and Mechanics

Abstract: Following a summary of our research activities related to optical imaging in scatter, super-resolution sensing, neuroscience, nanophotonics, and optomechanics, I present issues and questions regarding potential opportunity spaces for X-ray science, notably involving high spatial resolution and the forces exerted by scattered photons. Two relevant questions posed are: (i) What discoveries could be made by achieving a measurement spatial resolution that is very small relative to the X-ray wavelength and how might they be realized? (ii) How could X-ray forces on condensed matter be quantified and exploited? The concept of relative motion in structured illumination for achieving essentially unlimited spatial resolution at optical wavelengths is reviewed to consider whether X-ray analogues could be realized. With object motion in a coherent speckle field, super-resolution sensing and imaging through a thick and heavily scattering random medium are possible. Enhanced spatial information is possible with a random analyzer, and it appears that temporal coherence can be relaxed. Could scattered X-ray photons be similarly considered? The character of the electromagnetic force in condensed matter remains poorly understood, and, while optical experiments are challenging, the opportunity space for contributions and applications is enormous. Simulations and experimental results to probe optical forces in nanostructured media lead to a discussion of prospects for the measurement of the force due to X-rays scattering from a mirror, along with the development of a supporting theory. Could quantifying X-ray forces lead to improved experiments and new dimensions in X-ray science? This leads to the concluding discussion regarding whether new X-ray experiments can be designed to investigate related open questions.

Biography: Kevin has been a professor at Purdue University since 1990. Prior to joining Purdue, he was on the faculty of the University of Maryland, College Park, following completion of his Ph.D. from the University of Illinois in 1984. He is a Fellow of the Institute of Electrical and Electronics Engineers (IEEE), Optica (formerly the Optical Society of America), and the American Physical Society (APS). He grew up in Australia and founded the Purdue Karate Club in 1990. He has been a visiting professor at the Royal Institute of Technology, the Massachusetts Institute of Technology, the University of Melbourne, and the University of Canterbury.