Karl Alex Müller

Karl Alex Müller
Armin Kübelbeck · CC BY-SA 3.0 · source
Name	Karl Alex Müller
Birth date	1927-04-20
Birth place	Basel, Switzerland
Death date	2023-10-09
Death place	Zurich, Switzerland
Nationality	Swiss
Fields	Physics, Solid-state physics
Alma mater	ETH Zurich
Known for	Discovery of high-temperature superconductivity in oxides
Awards	Nobel Prize in Physics

Contents

Karl Alex Müller was a Swiss physicist notable for co-discovering high-temperature superconductivity in copper oxide ceramics, a breakthrough that reshaped research in condensed matter physics, materials science, and solid state physics. His collaborative work with Georg Bednorz led to rapid international efforts by laboratories such as Bell Labs, IBM Research, and university groups at University of Cambridge, Massachusetts Institute of Technology, and University of Tokyo to synthesize and characterize novel superconductors. The discovery precipitated a surge in experimental and theoretical activity spanning institutions like Max Planck Society, Lawrence Berkeley National Laboratory, and Argonne National Laboratory, and culminated in the award of the Nobel Prize in Physics.

Early life and education

Müller was born in Basel and raised in the context of Swiss academic culture that included institutions like ETH Zurich and the University of Basel. He completed his undergraduate and doctoral studies at ETH Zurich, where contemporaries and departments intersected with figures from Paul Scherrer Institute research and the broader European physics community, including contacts with researchers affiliated with CERN and Max Planck Institute for Solid State Research. During his education he encountered developments stemming from predecessors such as Heike Kamerlingh Onnes and colleagues influenced by work at places like University of Chicago and Columbia University.

Müller’s career included appointments at research centers and universities across Europe and engagements with industrial research organizations. He worked in laboratory environments connected to IBM Zurich Research Laboratory and pursued collaborations that interfaced with groups at ETH Zurich, the University of Geneva, and national facilities such as SINTEF and the Paul Scherrer Institute. His publications and seminars were discussed at international conferences including meetings hosted by International Union of Pure and Applied Physics and the American Physical Society. Müller investigated perovskite oxides and transition metal compounds, building on chemical syntheses and characterization techniques developed in laboratories like Los Alamos National Laboratory and Oak Ridge National Laboratory.

In collaboration with Georg Bednorz, Müller identified superconductivity at significantly higher temperatures in a barium-doped lanthanum copper oxide perovskite, an oxide ceramic distinct from previously known metallic superconductors pioneered by work tracing to Heike Kamerlingh Onnes and later theoretical frameworks from John Bardeen, Leon Cooper, and John Robert Schrieffer. The 1986 report triggered rapid confirmation by teams at institutions such as University of California, Berkeley, University of Alabama at Birmingham, University of Minnesota, and Stanford University. Theoretical implications engaged researchers influenced by models from Lev Landau, Philip W. Anderson, and J. M. Ziman, while experimental techniques invoked methods refined at Argonne National Laboratory and Los Alamos National Laboratory for resistivity, magnetization, and crystallography. For this work Müller and Bednorz were jointly awarded the Nobel Prize in Physics, which recognized their discovery’s profound impact on materials science and stimulated initiatives in applied research by companies like Siemens, General Electric, and Hitachi to explore superconducting applications.

Beyond the Nobel Prize in Physics, Müller received recognition from academic societies and institutions across Europe and North America. His honors included memberships in academies such as the Swiss Academy of Sciences and associations that interact with entities like the European Physical Society and American Association for the Advancement of Science. He delivered invited lectures at venues including the Royal Society and universities such as University of Cambridge, Harvard University, and Princeton University. Müller’s work was cited in award citations and commemorations by national research councils and foundations that include affiliations with ETH Zurich and the Max Planck Society.

Müller maintained connections to Swiss scientific institutions throughout his life, influencing generations of researchers at ETH Zurich, University of Zurich, and other European centers. His legacy lives on through research programs at facilities such as Paul Scherrer Institute and international collaborations spanning universities like University of Tokyo, Seoul National University, and Tsinghua University. The discovery he shared with Georg Bednorz accelerated the development of superconducting technology pursued by corporations and national laboratories including Siemens, Hitachi, Argonne National Laboratory, and Brookhaven National Laboratory. Memorials and retrospectives appeared in journals and institutions across the scientific community, with symposia organized by bodies such as the American Physical Society and the European Physical Society. His influence persists in ongoing investigations into unconventional superconductivity at establishments like Max Planck Institute for Solid State Research and in graduate programs at ETH Zurich and other universities that continue training researchers in condensed matter physics and materials science.