SμS: Swiss Muon Source
µSR - Muon Spin Rotation, Relaxation or Resonance: A research tool using muons as sensitive local magnetic probes in matter.
Research at the LMU focuses mainly on magnetic properties of materials and on positive muons or muonium (bound state of a positive muon and an electron) as light protons or hydrogen substitutes in matter.
Worldwide unique: The Low-Energy Muon Beam and µSR Spectrometer for the study of thin films, layers and surfaces, the possibility to perform high-field µSR with a field up to 9.5 Tesla, and the Extraction of Muons On Request for high frequency resolution and slow relaxation measurements.
Latest scientific SμS highlights:
Magnetic topological phases of quantum matter are an emerging frontier in physics and materials science, of which kagome magnets appear as a highly promising platform. Here, we explore magnetic correlations in the recently identified topological kagome system TbMn6Sn6 using muon spin rotation, combined with local field analysis and neutron diffraction. Our studies identify an out-of-plane ferrimagnetic structure with slow magnetic fluctuations which exhibit a critical slowing down below T*C1 ≃ 120 K and finally freeze into static patches with ideal out-of-plane order below TC1 ≃ 20 K....
Microscopic evidence for anisotropic multigap superconductivity in the CsV3Sb5 kagome superconductor
The recently discovered kagome superconductor CsV3Sb5 (Tc ≃ 2.5 K) has been found to host charge order as well as a non-trivial band topology, encompassing multiple Dirac points and probable surface states. Such a complex and phenomenologically rich system is, therefore, an ideal playground for observing unusual electronic phases. Here, we report anisotropic superconducting properties of CsV3Sb5 by means of transverse-field muon spin rotation (μSR) experiments.
Topological semimetals are three dimensional materials with symmetry-protected massless bulk excitations. As a special case, Weyl nodal-line semimetals are realized in materials having either no inversion or broken time-reversal symmetry and feature bulk nodal lines. The 111-family, including LaNiSi, LaPtSi and LaPtGe materials (all lacking inversion symmetry), belongs to this class. Here, by combining muon-spin rotation and relaxation with thermodynamic measurements, we find that these materials exhibit a fully- gapped superconducting ground state, while spontaneously breaking time-reversal symmetry at the superconducting transition.