
LNS: Laboratory for Neutron Scattering and Imaging
PhD, Master, Bachelor or Semester projects at the LNS
We offer students the possibility to do their PhD or educational research in our lab. See Teaching and Education for detailed information on Master/Diploma thesis, Bachelor/Semester work and practical courses at the LNS.
News
SANS-LLB at PSI: keeping up with the soft matter community needs
The shutdown of the Orphée reactor at LLB (Saclay, France) and the upgrade of the SINQ neutron guide system at PSI (Villigen, Switzerland) in 2019 were the beginning of a long-term collaboration between PSI and LLB. The SANS-LLB instrument, formerly known as PA20, has travelled more than 500 km, and since 2020 is being installed at SINQ/PSI as a collaborative effort between PSI and LLB. The aim is to make a modern SANS instrument available to the soft matter neutron scattering community at the SINQ spallation source.
Low-temperature magnetic crossover in the topological kagome magnet TbMn6Sn6
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....
Uniaxial pressure induced stripe order rotation in La1.88Sr0.12CuO4
Static stripe order is detrimental to superconductivity. Yet, it has been proposed that transverse stripe fluctuations may enhance the inter-stripe Josephson coupling and thus promote superconductivity. Direct experimental studies of stripe dynamics, however, remain difficult. From a strong-coupling perspective, transverse stripe fluctuations are realized in the form of dynamic “kinks”—sideways shifting stripe sections. Here, we show how modest uniaxial pressure tuning reorganizes directional kink alignment.
Square and rhombic lattices of magnetic skyrmions in a centrosymmetric binary compound
Magnetic skyrmions are topologically stable swirling spin textures with particle-like char- acter, and have been intensively studied as a candidate of high-density information bit. While magnetic skyrmions were originally discovered in noncentrosymmetric systems with Dzyaloshinskii-Moriya interaction, recently a nanometric skyrmion lattice has also been reported for centrosymmetric rare-earth compounds, such as Gd2PdSi3 and GdRu2Si2. For the latter systems, a distinct skyrmion formation mechanism mediated by itinerant electrons has been proposed, and the search of a simpler model system allowing for a better understanding of their intricate magnetic phase diagram is highly demanded. Here, we report the discovery of square and rhombic lattices of nanometric skyrmions in a centrosymmetric binary compound EuAl4, by performing small-angle neutron and resonant elastic X-ray scattering experiments.