Profile

Stephanie (Steffi) Diem is the principal investigator of the Pegasus-III Experiment, a fusion energy project focused on developing innovative startup techniques to reduce the cost and complexity of future fusion power plants. Her research centers on experimental plasma physics for fusion energy development, with an emphasis on validating numerical models using experimental data. She specializes in the use of radio-frequency waves to heat and drive current in magnetically confined plasmas and has led and contributed to experiments on a range of fusion devices in the United States and abroad. Her current work focuses on electron Bernstein wave heating and current drive on Pegasus-III at the University of Wisconsin–Madison, as well as on domestic and international collaborations on radio-frequency injection in fusion plasmas. Professor Diem earned her PhD in plasma physics from Princeton University and previously served as a research and development scientist at Oak Ridge National Laboratory, including a long-term assignment at the DIII-D National Fusion Facility.