Question: Which of the developer of STED microscopy is a Romanian-born German physicist and one of the directors of the Max Planck Institute for Biophysical Chemistry in Göttingen, Germany?

Context paragraphs:
Stefan Hell: Stefan Walter Hell (born 23 December 1962) is a Romanian-born German physicist and one of the directors of the Max Planck Institute for Biophysical Chemistry in Göttingen, Germany.  He received the Nobel Prize in Chemistry in 2014 "for the development of super-resolved fluorescence microscopy", together with Eric Betzig and William Moerner.

Max Planck Institute for Physics and Astrophysics: The Max Planck Institute for Physics and Astrophysics is a former institute of the Max Planck Society in Germany.  Located in Garching near Munich, it was home to scientists such as Werner Heisenberg.  The institute was founded in 1958 as a successor to the Max Planck Institute for Physics in Göttingen.  In 1991, it was split into two successor institutes, the current Max Planck Institute for Physics and Max Planck Institute for Astrophysics, both located in Garching.

STED microscopy: Stimulated emission depletion (STED) microscopy is one of the techniques that make up super-resolution microscopy.  It creates super-resolution images by the selective deactivation of fluorophores, minimising the area of illumination at the focal point, and thus enhancing the achievable resolution for a given system.  It was developed by Stefan W. Hell and Jan Wichmann in 1994, and was first experimentally demonstrated by Hell and Thomas Klar in 1999.  Hell was awarded the Nobel Prize in Chemistry in 2014 for its development.  In 1986, V.A. Okhonin (Institute of Biophysics, USSR Academy of Sciences, Siberian Branch, Krasnoyarsk) had patented the STED idea.  This patent was, perhaps, unknown to Hell and Wichmann in 1994.

Jens Frahm: Jens Frahm (born March 29, 1951 in Oldenburg, Germany) is Director of the Biomedizinische NMR Forschungs GmbH (Biomedical NMR Research Inc., not-for-profit) at the Max Planck Institute for Biophysical Chemistry in Göttingen, Germany.

Max Planck Institute of Biochemistry: The Max Planck Institute of Biochemistry is a research institute of the Max Planck Society located in Martinsried, a suburb of Munich.  The Institute was "founded in 1973 by the merger of three formerly independent institutes: the Max Planck Institute of Biochemistry, the Max Planck Institute of Protein and Leather Research (founded 1954 in Regensburg), and the Max Planck Institute of Cell Chemistry (founded 1956 in Munich)."

Max Planck Institute for Marine Microbiology: The Max Planck Institute for Marine Microbiology is located in Bremen, Germany.  It was founded in 1992, almost a year after the foundation of its sister institute, the Max Planck Institute for Terrestrial Microbiology at Marburg.  In 1996, the institute moved into new buildings at the campus of the University of Bremen.  It is one of 80 institute in the Max Planck Society (Max Planck Gesellschaft).

Max Planck Institute for Coal Research: The Max Planck Institute for Coal Research (German: "Max-Planck-Institut für Kohlenforschung" ) is an institute located in Mülheim an der Ruhr, Germany specializing in chemical research on catalysis.  It is one of the 80 institutes in the Max Planck Society ("Max-Planck-Gesellschaft").  Founded in 1912 as the Kaiser Wilhelm Institute for Coal Research ("Kaiser-Wilhelm-Institut für Kohlenforschung") in Mülheim an der Ruhr to study the chemistry and uses of coal, it became an independent Max Planck Institute in 1949.

Max Planck Institute for Biophysical Chemistry: The Max Planck Institute for Biophysical Chemistry (Karl Friedrich Bonhoeffer Institute) in Göttingen is a research institute of the Max Planck Society.  Currently, 850 people work at the institute, about half of them are scientists.

Klaus Weber: Klaus Weber (5 April 1936 – 8 August 2016) was a German scientist who made many fundamentally important contributions to biochemistry, cell biology, and molecular biology, and was for many years the director of the Laboratory of Biochemistry and Cell Biology at the Max Planck Institute for Biophysical Chemistry in Göttingen, Germany.

Hans Kuhn: Hans Kuhn (5 December 1919 – 25 November 2012) was a Swiss chemist.  He was professor emeritus for physical chemistry and former scientific director at the Max Planck Institute for Biophysical Chemistry (Karl Friedrich Bonhoeffer Institute) in Göttingen.

Supporting paragraphs: STED microscopy Stefan Hell
Answer: Stefan Walter Hell