APhMS Special Seminar

**Refreshments outside Noyes 153 at 3:45pm

Abstract:

Classical and quantum light sources play a fundamental role in science and technology from laser fusion, to communication, manufacturing, defense, sensing, medicine, or quantum computing. Fundamental challenges have prevented the "scaling" of light sources. For example, efficiently scaling the power of lasers has always come at the cost of single mode operation, a question that has been investigated, without success, since the invention of lasers in 1958. In the first part of the talk, I will propose a solution to this question with a "scale-invariant" laser that remains single mode irrespective of its cavity size. I will show that the strategy discovered goes beyond the Schawlow-Townes two-mirror approach that is used by all existing lasers. I will conclude that our solution overcomes a more than six-decade challenge in wave-physics and that mirrors are bad for the scaling of lasers [1-2]. I may also briefly discuss topological light sources that we pioneered [3-5]. In the second part of the talk, I will discuss our recent and surprising introduction of silicon as a programmable material platform for quantum optics with potential applications in future quantum networks/computers [6-7].

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. Kanté, "BerkSEL: A scale-invariant laser beyond the Schawlow-Townes two-mirror strategy," Nat Commun 15, 2047 (2024).

3- 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).

4- B. Bahari, L. Hsu, S. H. Pan, D. Preece, A. Ndao, A. El Amili, Y. Fainman, and B. Kanté, "Photonic quantum Hall effect and multiplexed light sources of large orbital angular momenta," Nature Physics 17, 700-703 (2021).

5- 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).

6- W. Redjem, Y. Zhiyenbayev, W. Qarony, V. Ivanov, C. Papapanos, W. Liu, J. Jhuria, Z. Y. Al Balushi, S. Dhuey, A. Schwartzberg, L. Z. Tan, T. Schenkel, and B. Kanté, "All-silicon quantum light source by embedding an atomic emissive center in a nanophotonic cavity," Nature Communications 14, 3321 (2023).

7- K. Jhuria, V. Ivanov, D. Polley, Y. Zhiyenbayev, W. Liu, A. Persaud, W. Redjem, W. Qarony, P. Parajuli, Q. Ji, A. J. Gonsalves, J. Bokor, L. Z. Tan, B. Kanté and T. Schenkel, "Programmable quantum emitter formation in silicon," Nat Commun 15, 4497 (2024).

More about the Speaker:

Boubacar Kanté is the Chenming Hu 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). He is also a co-Director of the Berkeley Emerging Technology Research Center (BETR). He received a Ph.D degree in Engineering/Physics from "Université Paris-Saclay" (Orsay-France) in 2010. 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 materials, wave-matter interaction, and optoelectronics.

Boubacar Kanté received the 2024 Bakar Prize. He 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.