Dr. Umstadter studied laser-driven electron accelerators for his Ph.D. dissertation in physics at the University of California, Los Angeles. He then developed laser generated x-ray sources during a postdoc at Bell Laboratories. As a professor at the University of Michigan, he researched relativistic nonlinear optics with ultrahigh-intensity lasers. Dr. Umstadter was appointed Olson Professor in the Physics and Astronomy Department at the University of Nebraska–Lincoln, where he founded the Extreme Light Laboratory, now home of the petawatt-peak-power Diocles laser. He uses Diocles to study the physics and applications of novel laser-driven hyper-spectral radiation sources. He is a fellow of the American Physical Society (APS), and in 2008 he was recognized as an APS Outstanding Referee.