Event announcement as pdf-Download (https://tu-dresden.de/mn/phys ik/ressourcen/dateien/physikalisches-kolloquium/2025-10-28-Phys_Kolloq-Esc hrig-WiSe2025.pdf).
Abstract: Superconducting spi ntronics is based on spin-polarized Cooper pairs\, which appear near the i nterfaces between superconducting and magnetic materials. In the case of a Josephson device containing a strongly spin-polarized itinerant ferromagn et\, only Cooper pairs with equal spin relative to the spin quantisation a xis contribute over appreciable distances. Typically\, the conversion proc ess from spin-singlet to equal-spin pairs requires non-collinear magneti c inhomogeneities in the vicinity of the interface. If the spin texture in the Josephson junction is also non-coplanar\, a distinctive Josephson Di ode Effect appears. This effect is driven by spin-geometric phases that en ter the current-phase relation in a novel way. In the case of a spatially slowly varying magnetization profile\, they enter via an effective U(1) ga uge field that couples with opposite sign to the two spin projections. Thi s opens up the field to an entire new set of phenomena related to the inte rplay between spin-geometric phases and Josephson phases. I present an ove rview over these novel functionalities.
Short bio: Matthias Eschrig studied Physics at the Universities of Leipzig and Bayr euth\, and completed his Ph.D. at the University of Bayreuth\, Germany\, i n 1997. After postdoctoral research in the U. S. at Northwestern Universit y (1997-1999) and at Argonne National Laboratory (1999-2001)\, he moved to University of Karlsruhe (since 2009 Karlsruhe Institute of Technology) in Germany\, where he stayed from 2001-2010\, and where he completed his Hab ilitation Degree in 2005. After guest professorships at University of Kons tanz in 2007 and 2009-2010\, he joined the faculty at Royal Holloway\, Uni versity of London in November 2010\, where he was promoted to Full Profess or in January 2012. In 2019\, he accepted the offer of a Chair in Condense d Matter Theory at University of Greifswald. He acted as founding member a nd co-director of the Hubbard Theory Consortium\, as founding member of th e Baltic Consortium of Theoretical Physics\, as Fellow of the South East P hysics Network (SEPnet)\, and as member of the Board of Governors of the I nternational Institute for Complex Adaptive Matter. In 2015 he was awarded the Lars Onsager Guest Professorship and Lars Onsager Medal of the Norweg ian University of Technology.