Scientific Highlights
Spin Liquid State in the 3D Frustrated Antiferromagnet PbCuTe2O6: NMR and Muon Spin Relaxation Studies
PbCuTe2O6 is a rare example of a spin liquid candidate featuring a three-dimensional magnetic lattice. Strong geometric frustration arises from the dominant antiferromagnetic interaction that generates a hyperkagome network of Cu2+ ions although additional interactions enhance the magnetic lattice connectivity.
Origin of the Spin-Orbital Liquid State in a Nearly J=0 Iridate Ba3ZnIr2O9
We show using detailed magnetic and thermodynamic studies and theoretical calculations that the ground state of Ba3ZnIr2O9 is a realization of a novel spin-orbital liquid state. Our results reveal that Ba3ZnIr2O9 with Ir5+ (5d4) ions and strong spin-orbit coupling (SOC) arrives very close to the elusive J 1⁄4 0 state but each Ir ion still possesses a weak moment.
Coexistence of low-moment magnetism and superconductivity in tetragonal FeS and suppression of Tc under pressure
The family of iron-based superconductors has recently acquired a new member material, FeS. Theoretically, this compound has been shown to have electronic structure similar to that of the superconducting FeSe. However, contradictory ground states have been predicted for FeS. In this work, a collaboration of authors from Switzerland and Germany use muon spin rotation and relaxation to show that weak-moment magnetism microscopically coexists with bulk superconductivity.
Georgian Order of Honor for Zurab Guguchia
Thomas Prokscha from Laboratory for the Muon Spin Spectroscopy LMU and Head of the LEM Group was invited to serve an additional year as a member of the INTC Committee (ISOLDE and Neutron Time-of-Flight Experiments Committee) at CERN.
The INTC evaluates proposals for experiments on the ISOLDE facility. In addition it reviews the experiments proposed for the neutron time-of-flight facility.
Rate of Molecular Transfer of Allyl Alcohol across an AOT Surfactant Layer Using Muon Spin Spectroscopy
The transfer rate of a probe molecule across the interfacial layer of a water-in-oil (w/o) microemulsion was investigated using a combination of transverse field muon spin rotation (TF-μSR), avoided level crossing muon spin resonance (ALC-μSR), and Monte Carlo simulations. Reverse micro-emulsions consist of nanometer-sized water droplets dispersed in an apolar solvent separated by a surfactant monolayer.
Strong enhancement of s-wave superconductivity near a quantum critical point of Ca3Ir4Sn13
We report microscopic studies by muon spin rotation/relaxation as a function of pressure of the Ca3Ir4Sn13 and Sr3Ir4Sn13 cubic compounds, which are members of the (Ca1−xSrx)3Ir4Sn13 system displaying superconductivity and a structural phase transition associated with the formation of a charge density wave (CDW).
Direct evidence for a pressure-induced nodal superconducting gap in the Ba0.65Rb0.35Fe2As2 superconductor
The superconducting gap structure in iron-based high-temperature superconductors (Fe-HTSs) is non-universal. In contrast to other unconventional superconductors, in the Fe-HTSs both d-wave and extended s-wave pairing symmetries are close in energy. Probing the proximity between these very different superconducting states and identifying experi- mental parameters that can tune them is of central interest.
Intrinsic Paramagnetic Meissner Effect Due to s-Wave Odd-Frequency Superconductivity
In 1933, Meissner and Ochsenfeld reported the expulsion of magnetic flux - the diamagnetic Meissner effect - from the interior of superconducting lead. This discovery was crucial in formulating the Bardeen-Cooper-Schrieffer (BCS) theory of superconductivity. In exotic superconducting systems BCS theory does not strictly apply.
Remotely induced magnetism in a normal metal using a superconducting spin-valve
Superconducting spintronics has emerged in the past decade as a promising new field that seeks to open a new dimension for nanoelectronics by utilizing the internal spin structure of the superconducting Cooper pair as a new degree of freedom. Its basic building blocks are spin-triplet Cooper pairs with equally aligned spins, which are promoted by proximity of a conventional superconductor to a ferromagnetic material with inhomogeneous macroscopic magnetization.