EECS Colloquium

Wednesday, September 21, 2022

306 Soda Hall (HP Auditorium)
4:00 – 5:00 pm

 Youtube Webinar

Eli Yablonovitch

Professor Emeritus, EECS
Professor in the Graduate School
UC Berkeley

Eli Yablonovitch speaks on "Physics does Constrained Optimization (for Free); A New Approach Toward Computation" (9/21/22)


Optimization is vital to Engineering, Artificial Intelligence, and to many areas of Science.  Now new circuit principles of computation are emerging, for Artificial Intelligence and Optimization, based on Onsager’s Principle of Minimum Entropy Generation (1931, Nobel Prize 1968). We call this Onsager Computing, as opposed to conventional Von Neumann Computing. Electrical Onsager Computers run ~10000x faster; and have ~10000x less energy-to-solution, than conventional machines. Furthermore, optical Onsager machines could provide an additional 1000x increase in speed.


Prof. Yablonovitch introduced the idea that strained semiconductor lasers could have superior performance due to reduced valence band (hole) effective mass. With almost every human interaction with the internet, optical telecommunication occurs by strained semiconductor lasers. He is regarded as a Father of the Photonic BandGap concept, and he coined the term “Photonic Crystal”. The geometrical structure of the first experimentally realized Photonic bandgap is sometimes called “Yablonovite”. In his photovoltaic research, Yablonovitch introduced the 4(n squared) (“Yablonovitch Limit”) light-trapping factor that is in worldwide use, for almost all commercial solar panels. His mantra that “a great solar cell also needs to be a great LED”, is the basis of the world record solar cells: single-junction 29.1% efficiency; dual-junction 31.5%; quadruple-junction 38.8% efficiency; all at 1 sun.

Video of this Presentation