This week's speaker is:

MinJae Kim, Ph.D. Student, Stanford University
"Towards Sustainable Light Source: Ultra-efficient Organic Light-emitting Diodes for Sustainable Displays and Lighting"

Abstract:

Organic light-emitting diodes (OLEDs) have been widely used in displays thanks to the exceptionally high contrast ratio, color purity, and flexibility. As a planar light source capable of rendering a full color gamut, much effort has been devoted and succeeded to developing a highly efficient emitter with its efficiency reaching near-unity. However, the ability of the emitter to convert an exciton into a photon is shadowed by the device efficiency, typically limited to ~ 20% due to a substantial portion of light subject to parasitic loss and total internal reflections at the interfaces within the stratified organic layer in OLEDs. The light trapped within the OLED not only limits the efficiency per se but also ultimately leads to heat, further aggravating the efficiency. This significant light loss in OLEDs, combined with the global electricity power consumption for lighting and displays, which spans 20–25% of the global power, poses a significant challenge towards sustainable light sources. This talk will highlight the recent developments in technologies to ‘extract’ light confined within the device and the challenges arising from bulkiness, large aperture ratio, and optical crosstalk. To illustrate the room for further opportunities in this space, this talk will describe the work of MinJae Kim and his colleagues, leveraging trans-scale optical optimization of both OLED stack and light outcoupling structure designs.

Bio:
MinJae Kim is a PhD student in Materials Science and Engineering at Stanford University. He received a BS in Materials Science and Engineering at KAIST. Before joining Stanford University, he was a National Presidential Science Scholar, KAIST Presidential Fellow, National University of Singapore (NUS) Young Fellow, and Young Future Energy Leader selected by Khalifa University. He has received many awards and honors, including the national delegation at the Lindau Nobel Laureate Meeting, the Talent Award of Korea, and the membership in the Young Engineers’ Honor Society nominated by the National Academy of Engineering of Korea.

The topics of this seminar are broad but typically fall under technologies’ scaling potential and impact on (the system of) people, the environment and the economy. A particular focus is placed on the interaction potential of technologies with the energy, water, and material systems. Our goal is to create an intimate, collaborative space for students, postdocs, scientists, and PIs within Stanford across micro-level (material and technology) to macro-level (system) interests. These seminars will provide an opportunity to disseminate insights from your studies, connect with fellow researchers, and strengthen bonds across the community.