From January 2009 until April 2013 Dr. Chu served as the 12th U.S. Secretary of Energy under President Barack Obama.  In this position he began several initiatives including ARPA-E (Advanced Research Projects Agency – Energy), the Energy Innovation Hubs, and the Clean Energy Ministerial meetings.

From 2004-2009, he was the Director of the Lawrence Berkeley National Laboratory and Professor of Physics and Professor of Molecular and Cell Biology at the University of California Berkeley. Prior to those positions, he was the Theodore and Francis Geballe Professor of Physics and Applied Physics at Stanford University. During this time at Stanford (1987 – 2004) he twice chaired the Department of Physics and helped start Bio-X, a multi-disciplinary initiative that brings together the physical and biological sciences with engineering and medicine.

Chu’s thesis and postdoctoral work was one of the first successful observations of parity non-conservation in atomic transitions, confirming the Weinberg-Salam-Glashow theory that unified weak and electromagnetic interactions. While at Bell Laboratories Chu and A. Mills performed the first laser spectroscopy of positronium, the fundamental atom consisting of an electron and the positron, and muonium, an atom consisting of a proton and muon. While also at Bell Labs, Chu also made contributions in condensed matter studies of exciton energy transfer, Anderson Localization, and made the first observation of anomalous (faster than light and negative velocity) pulse propagation.