PI

Archana Raja

Dr. Archana Raja is a Staff Scientist at Lawrence Berkeley National Laboratory. She studies how interfaces control the flow and transformation of energy, charge, and information in quantum materials. Interfaces are where light becomes charge, where charge transfers energy to the lattice, and where spin and other carriers of information are processed.

Her team pairs optical spectroscopy and microscopy with ultrafast electron diffraction and electron energy-loss spectroscopy to study interfaces as they really are, with their defects, strain, disorder, and atomic reconstruction. This combination produced the first sub-nanometer imaging of excitons within a single moiré unit cell and revealed how charge transfer across a 2D interface hands energy to the lattice. Early in her career, she showed that an atomically thin semiconductor responds to its surroundings much like a molecule in a solvent, allowing its band gap to be tuned through the dielectric environment. She supports the Molecular Foundry’s national and international user community, helping researchers around the world to apply these techniques to their own scientific problems.

AI extends this approach. As multimodal datasets grow richer, the challenge shifts from acquiring complementary measurements to interpreting them together and deciding what to measure next, since each measurement is expensive and time-consuming. With collaborators, Raja introduced LEAP-Bench, a benchmark that tests whether AI agents can reason from raw instrument data to scientific conclusions across multiple measurement modalities. This work is central to LEAP (Low-Energy, AI-Informed Phase Transitions), a University of California AI Science at Scale initiative. Raja is co-PI and Project Integration Officer of the initiative, and co-PI on the DOE Genesis Mission projects CASCADE and AlphaFold for Microelectronics.

Raja earned her PhD in Chemical Physics at Columbia University with Tony Heinz and Louis Brus, and her integrated MSc in Chemistry at IIT Bombay, where she received the Institute Silver Medal. She held postdoctoral appointments at Stanford University and at UC Berkeley, the latter as a Heising-Simons Junior Fellow. At Berkeley Lab, she received the 2023 Lab Director’s Award for Exceptional Achievement in Early Scientific Career.

Honors · LBNL Director's Award for Exceptional Early Scientific Career (2023) · Early Career LDRD Award (2020–22) · Heising-Simons Junior Fellowship, Kavli ENSI (2017–19) · IIT Bombay Institute Silver Medal