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Optica Names Stephan Schlemmer the 2023 William F. Meggers Award Recipient


Optica (formerly OSA), Advancing Optics and Photonics Worldwide, is pleased to announce that Stephan Schlemmer, Universität zu Köln, Germany, has been selected as the 2023 recipient of the William F. Meggers Award. Schlemmer is recognized for pioneering ultra-sensitive action spectroscopy with fundamental applications to spectra of molecular ions, particularly CH5+, and their key roles in astrochemistry.

Schlemmer received his Ph.D. 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.

Established in 1970, the Meggers Award is presented for outstanding work in spectroscopy. It honors William F. Meggers for his notable contributions to the field of spectroscopy and metrology, and was endowed by the family of William F. Meggers, several individuals and a number of optical manufacturers.

About Optica

Optica (formerly OSA), Advancing Optics and Photonics Worldwide, is the society dedicated to promoting the generation, application, archiving and dissemination of knowledge in the field. Founded in 1916, it is the leading organization for scientists, engineers, business professionals, students and others interested in the science of light. Optica's renowned publications, meetings, online resources and in-person activities fuel discoveries, shape real-life applications and accelerate scientific, technical and educational achievement. Discover more at:

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