Report summary

University of California, Berkeley Department of Physics in 2015-2026 reads as a 120-PI network with 180 internal PI collaborations. The dominant subject mix is Physics and Astronomy as the leading field (55% of slots across 98 PIs; 98 labels), Atomic and Molecular Physics, and Optics as the leading subfield (19% of slots across 45 PIs; 45 labels), and Particle physics theoretical and experimental studies as the leading topic (6% of slots across 22 PIs; 22 labels). That is promising: collaboration is not just one large hairball, and the leading breakdown groups cover 29 PIs across distinct clusters. The leading PI names are Stephen R. Leone (52.4 weighted works; Laser-Matter Interactions and Applications, Spectroscopy and Quantum Chemical Studies); Xiang Zhang (51.8 weighted works; 2D Materials and Applications, Metamaterials and Metasurfaces Applications). The most visible ties are Michael F. Crommie and Feng Wang (44 shared works, weight 21.1); Alex Zettl and Michael F. Crommie (45 shared works, weight 19.4). The leading breakdown groups are group 1 with 10 PIs, 15 internal connections, weight 134, around Materials Chemistry, Electrical and Electronic Engineering, Atomic and Molecular Physics, and Optics, led by Xiang Zhang, Alex Zettl, Feng Wang; group 2 with 10 PIs, 13 internal connections, weight 19.8, around Nuclear and High Energy Physics, Atomic and Molecular Physics, and Optics, Astronomy and Astrophysics, led by Raphael Bousso, Yasunori Nomura, Jeff A. Dror.