Colloquium: Dr. Amr Shaltout, Ph.D. Stanford University, Geballe Laboratory for Advanced Materials
All dates for this event occur in the past.
Title:
Spatiotemporal Light Control with Active Metasurfaces
Details:
Tuesday, March 26
10:00 a.m. – 11:00 a.m.
Dreese Lab, Room 260
Abstract
In optics, researchers are continuously trying to find new ways to manipulate the intrinsic properties of light, such as the direction, polarization state, and frequency. Currently, this is accomplished using relatively bulky optical elements, such as lenses, gratings, polarization filters and non-linear crystals. However, a new class of optical elements termed metasurfaces is emerging. Metasurfaces are essentially two-dimensional, flat optical elements composed of a dense array of nano-structured particles, called optical antennas. They can achieve many of the same functions as their bulky counterparts, but also provide new opportunities. They offer remarkable ways to manipulate light by locally controlling the amplitude, phase and/or polarization of optical wave-fronts. However, most of these optical elements are passive and their functions are set in stone during the fabrication process.
In my research, I am exploring ways to extrapolate the field of passive metasurface and build, new, active metasurface-devices. This is motivated by the notion that space and time play complementary roles in Maxwell’s equations. This suggests that structuring of materials in both space and time can bring forth exciting new physical phenomena and further broaden the device applications. I show that concepts from nanotechnology and ultrafast laser physics can be effectively combined to achieve control over light beams with high spatiotemporal precision. The emergence of active metasurfaces is very timely given the many applications that would benefit from tunable, flat, and easy-to-integrate optical elements. These include a variety of wearables, on-chip LIDAR, augmented/virtual reality, sensing, computational imaging and display technologies.
Bio
Dr. Amr Shaltout is a postdoctoral scholar at the Geballe Lab for Advanced Materials, Stanford University. He received his Ph.D. from the Department of Electrical and Computer Engineering, Purdue University in December 2015. His research interests are in the area of nanophotonics, where he focuses on optical metasurfaces for spatiotemporal and ultrafast light control that underlie neural computation.