Tribute to the memory of Peter Wachter
Peter Wachter, Professor at the Department of Physics of ETH Zurich until 1999, passed away on October 26, 2025, at the age of 94.
Peter Wachter studied physics at the Technical University of Munich, graduating in 1956 and completing his doctorate in 1960. He then spent two years as an assistant professor at the Radiation and Solid State Laboratory of New York University. From 1963, he worked at the Laboratory for Solid State Physics at ETH Zurich in the field of ferromagnetic semiconductors, initially as a research assistant, later as a senior research assistant, and after receiving his habilitation in 1969, as a lecturer. In 1972, the Swiss Federal Council appointed Peter Wachter as associate professor of experimental solid state physics at ETH Zurich. In 1973, he was promoted to full professor in the same field. He was also invited to spend semesters as a visiting professor in France, the USSR, China, and Japan. In 1987, he was elected President of the Magnetism Section of the European Physical Society.
Peter Wachter’s research activities spanned numerous fields at the forefront of new-materials based solid state physics, including emphasis on related /associated materials synthesis and crystal growth. He was among the pioneers of these fields, and developed, cultivated and refined a broad spectrum of experimental methods in a creative and topic-specific manner, including various optical spectroscopies and transport measurements. In 1964 he discovered the so-called “Busch-Wachter effect,” internationally known as the “red shift of ferromagnetic semiconductors”. Examples of other focused areas of research include intermediate-valence rare-earth compounds, heavy fermions, charge and spin density waves, superconductivity at high temperatures, excitons, Kondo effect, and the physics of low-dimensional materials. In general, Peter Wachter’s research topics may be placed within the broad context of strongly correlated electron systems.
Peter Wachter was a great colleague and as a successful mentor and teacher he made outstanding contributions to the training and development of young talents. He was known for his humour and generosity, and gave his staff considerable freedom in shaping their research interests and initiatives. While he was not himself member of MaNEP, he did support the membership of several senior and adjunct scientists of his staff at ETH Zurich to that condensed matter community in Switzerland. His strong culture of discussion was equally effective and inspiring. Colleagues and friends will remember him with appreciation and gratitude, and will keep him in honorable memory.
Bertram Batlogg and Leonardo Degiorgi
