CONFÉRENCE ANNULÉE POUR CAUSE DE GRÈVE ÉTUDIANTE
Abstract- Lasers play a fundamental role in science and technology from quantum computing, to communications, sensing, and imaging. The scaling of lasers and in-particular of surface emitting lasers is a multi-decade long question that has been investigated since the invention of lasers in 1958. In the first part of the talk, I will argue that a surface emitting laser that remains single mode irrespective of its size, should of necessity also waste light at the edge. This is a fundamental departure from the Schawlow-Townes two-mirror strategy that preserves gain and minimizes loss by keeping light away from mirrors. The strategy was implemented in our recent discovery of the Berkeley Surface Emitting Laser (BerkSEL) [1]. In the second part of this talk, I will discuss our invention of functional topological lasers: integrable non-reciprocal coherent light sources as well as compact bound state in continuum sources [1-2].
References.
1- R. Contractor, W. Noh, W. Redjem, W. Qarony, E. Martin, S. Dhuey, A. Schwartzberg, and B. Kanté, “Scalable single-mode surface emitting laser via open-Dirac singularities,” Nature 608, 692–698 (2022).
2- B. Bahari, A. Ndao, F. Vallini, A. El Amili, Y. Fainman, B. Kanté, “Nonreciprocal lasing in topological cavities of arbitrary geometries,” Science 358, 636-640 (2017).
3- A. Kodigala, T. Lepetit, Q. Gu, B. Bahari, Y. Fainman, and B. Kanté, “Lasing Action from Photonic Bound States in Continuum,” Nature 541, 196 – 199 (2017).
Bio- Boubacar Kanté is a Professor of Electrical Engineering and Computer Sciences (EECS) at the University of California Berkeley and a faculty scientist at the materials science division (MSD) of the Lawrence Berkeley National Laboratory (LBNL). In 2010, he received a Ph.D degree in Engineering/Physics from “Université de Paris Sud” (Orsay-France). He was assistant professor and then associate professor of Electrical and Computer Engineering (ECE) at UC San Diego from 2013 to 2018. His research interests include wave-matter interaction and nano-optics.
Boubacar Kanté is a 2021 Bakar Fellow and a 2020 Moore Inventor Fellow. He received the 2017 Office of Naval Research (ONR) Young Investigator Award, the 2016 National Science Foundation (NSF) Career Award, The best undergraduate teacher award from UC San Diego Jacob School of Engineering in 2017, the 2015 Hellman Fellowship, the Richelieu Prize in Sciences from the Chancellery of Paris Universities for the best Ph.D in France in Engineering, Material Science, Physics, Chemistry, Technology in 2010, the Young Scientist Award from the International Union of Radio Science (URSI) in Chicago in 2007, the Fellowship for excellence from the French Ministry of Foreign Affairs in 2003 for his undergraduate studies, a Research Fellowship from the French Research Ministry for his Ph.D studies.