Tunable and Reconfigurable Plasmonics and Metamaterials for Beam Shaping

Date(s):

Location:
CMRR Auditorium

Sponsored By:
Professor Zhaowei Liu

Speaker(s):
Yongmin Liu, Ph.D.
Department of Electrical and Computer Engineering
Northern University, Boston, USA
Yongmin Liu, Ph.D.

Abstract:

Plasmonics has become a very vibrant research area in nano optics. It allows us to concentrate, guide, and manipulate light at the deep subwavelength scale, promising enhanced light-matter interaction, next-generation optical circuits, sub-diffraction-limited imaging, and ultrasensitive biomedical detection. Furthermore, the assembly of rationally designed metallic structures can be used to construct metamaterials and metasurfaces with exotic properties and functionalities, including anomalous refraction/reflection, strong chirality and invisibility cloak. There is a pressing need of tunability and reconfigurability for plasmonics and metamaterials, in order to perform distinct functionalities and miniaturize the device footprint. In this talk, I will present our recent work in tunable and reconfigurable plasmonics and metamaterials. First, I will discuss the first demonstration of reconfigurable plasmonic lenses operating in microfluidic environment, which can dynamically diverge, collimate and focus surface plasmons. Second, I will present a designer metasurface that can efficiently control the polarization of Smith-Purcell emission of moving charged particle by coupling the inherent electric and magnetic dipoles of the metasurface. Finally, I will discuss origami-based, dual-band chiral metasurfaces at microwave frequencies. The flexibility in folding the metasurface provides another degree of freedom for geometry control in the third dimension, which induces strong chirality from the initial, 2D achiral structure. These results open a new avenue towards lightweight reconfigurable meta-devices.

Speaker Bio:
Yongmin Liu, Ph.D. obtained his Ph.D. from the University of California, Berkeley in 2009. He joined the faculty of Northeastern University at Boston in fall 2012 with a joint appointment in the Department of Mechanical & Industrial Engineering and the Department of Electrical & Computer Engineering. Dr. Liu’s research interests include nano optics, nanoscale materials and engineering, plasmonics, metamaterials, biophotonics, and nano optomechanics. He has authored and co-authored about 60 journal papers, including Science, Nature, Nature Nanotechnology, Nature Communications, Physical Review Letters and Nano Letters. Dr. Liu was a recipient of NSF CAREER Award (2017), Office of Naval Research Young Investigator Award (2016), SPIE DCS Rising Researcher Award (2016), 3M Non-Tenured Faculty Award (2016), Air Force Summer Faculty Fellowship (2015), and Chinese Government Award for Outstanding Students Abroad (2009). Currently he serves as an editorial board member for Scientific Reports, EPJ Applied Metamaterials and Nano Convergence.

Contact:
Julie Moritz (jmoritz@eng.ucsd.edu)