Classical and quantum light sources play a fundamental role in science and technology from quantum computing, to communications, manufacturing, defense, sensing, medicine, or imaging. However, scaling the power of lasers has always come at the cost of single mode operation, a scaling 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 and discuss a “scale-invariant” laser that remains single mode irrespective of its cavity size. I will show that the discovered strategy, named Berkeley Surface Emitting Laser (BerkSEL), goes beyond the Schawlow-Townes two-mirror strategy that is used by all existing lasers. I will conclude that mirrors are bad for the scaling of lasers [1]. I will also briefly discuss topological lasers that my group pioneered [2-4]. In the second part of the talk, I will discuss a scalable quantum optics platform fully based on silicon with potential applications in future quantum networks [5].

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- 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).
4- 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).
5- 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).