Date/Time
Date(s) - 12/03/2024
3:00 pm - 4:00 pm
Location
Rhines 125
Categories
Abstract
Mesoscale-ordered structures in polymers and soft materials have a myriad of applications in controlling the transport of matter, electrons, or photons. Controlling light propagation with polymers is challenging because photons are sensitive to structural defects; polymers often develop numerous defects due to uncontrolled nucleation and growth.
The first part of this talk will be about an ongoing effort to achieve defect-controlled aperiodic nanostructures in block copolymer thin films using directed self-assembly to control light propagation. Inspired by graphoepitaxy and pattern multiplication strategies used to achieve periodic ordered structures without defects, we investigated if the same principle applies to obtaining aperiodic quasicrystalline structures with controlled defects.
In the second part, I will introduce a project on developing security features using polymer composites consisting of bottlebrush block copolymer photonic crystals and chiral lanthanide complexes. Dual optical responses of the composite materials and their potential applications for hard-to-clone security features utilizing the intrinsic random placement of the optical components will be discussed.
Bio
Kyungtae Kim, Ph.D.
R&D Staff Scientist, Center for Integrated Nanotechnologies
Los Alamos National Laboratory
Dr. Kyungtae Kim is an R&D Scientist at the Center for Integrated Nanotechnologies (CINT) at Los Alamos National Laboratory. Kyungtae received his B.S. in Chemistry (Magna cum Laude) and Ph.D. in Polymer Chemistry from Pohang University of Science and Technology (POSTECH), South Korea. His Ph.D. research involved quantitative nanostructure analysis of functional polymer thin films for electronics applications.
He then moved to the United States to continue his research career as a postdoc at the University of Minnesota, working with Prof. Frank Bates and Prof. Chris Macosko. At Minnesota, Kyungtae studied complex ordered structures in diblock copolymers, known as Frank-Kasper phases, by following metallurgy-mimic processing pathways. In addition, he elucidated processing-dependent morphology and oxygen barrier properties of commercial polyolefins. At CINT, Kyungtae is expanding his research towards defect control and advanced manufacturing of block copolymers and polymer composite materials for national security applications. When not tackling polymer problems, Kyungtae plays tennis and enjoys the beautiful scenery of northern New Mexico.