We welcome today Dr. Oliver Breunig from the Institute of Physics II at the University of Cologne, hosted by TWIST. He will give a talk on “Gigantic Negative Magnetoresistance in a Disordered Topological Insulator”.
Details: “Recently the phenomenon of negative magnetoresistance (MR) is attracting renewed interest due to its occurrence in Weyl semimetals because of the chiral anomaly. In other systems a large MR typically relates to magnetism. In this talk a novel mechanism leading to a large negative MR will be presented that is based not on magnetism, but on disorder. In the newly synthesized bulkinsulating topological insulator material T1BixSb1-xTe2 we find a suppression of the resistivity by up to 98 % in 14 T at low temperature. From transport data and numerical simulations, this gigantic negative MR is understood by a percolation of charge puddles formed in the disordered bulk.”
Joo-Von Kim from the Centre for Nanoscience and Nanotechnology/CNRS/Université Paris-Sud in Orsay arrived for his two-month stay as a guest scientist in the INSPIRE group. He will use his expertise in micromagnetic simulations to work with Bertrand Dupé on the coupled motion of (anti)skyrmion pairs in magnetic ultrathin films ("Skyrmion Tango"). His stay is financially supported by the DAAD.