Stephan Schlemmer received his PhD from the University of Göttingen, Germany and was a postdoctoral fellow at the University of California, Berkeley, USA and Universita di Perugia, Italy. He is currently a professor of experimental physics at Universität zu Köln. He has also held positions at Leiden University, Netherlands and Chemnitz University of Technology, Germany

He specializes in molecular physics with an emphasis on high-resolution IR and THz spectroscopy, reaction dynamics, astrophysics, and astrochemistry. He pioneered the development of several novel spectroscopy tools and utilized them to address long standing spectroscopic problems.

One of Schlemmer’s major contributions to the field was his invention of action spectroscopy, which enables ion spectroscopy to be conducted with unparalleled sensitivity and resolution.

He received the William F. Meggers Award.