LNS: Laboratory for Neutron Scattering
The Laboratory for Neutron Scattering (LNS) at the Paul Scherrer Institute is responsible for the scientific exploitation, operation and development of neutron scattering instruments at the Swiss Spallation Neutron Source (SINQ). The team of 35 senior scientists, postdoctoral researchers and PhD students further collaborates on diverse research projects ranging from modern topics in condensed matter physics and materials science to pressing questions in energy research and health care. read moreWe offer students the possibility to do their educational research at our facilities. See Teaching and Education for detailed information on Master/Diploma thesis, Bachelor/Semester work and practical courses at the LNS. Currently we have two open positions for Master thesis projects: Spin and orbital liquids in frustrated spinels AB2X4 and Monopole hopping mechanism in spin ice.
2. May 2012
Direct observation of the quantum critical point in heavy fermion CeRhSi3
N. Egetenmeyer et al., Physical Review Letters 108, 177204 (2012). In many heavy fermion materials the quantum critical point is masked by superconductivity and it can only be detected by use of a local probe. In the noncentrosymmetric heavy fermion CeRhSi3 the ground state at ambient pressure is antiferromagnetically ordered and superconductivity sets in above 12 kbar coexisting with antiferromagnetism. We have unraveled a magnetic quantum critical point hidden deep inside the superconducting state of CeRhSi3. Using the muon spin rotation technique we observed the suppression of the internal fields at the lowest measured temperature, upon increase of external pressure. Our data suggest that the ordered moments are gradually quenched with increasing pressure. At 23.6 kbar, the ordered magnetic moments are fully suppressed via a second-order phase transition, and TN is zero.2. April 2012
Ellipsoidal hybrid magnetic microgel particles with thermally tunable aspect ratios
V. Städele et al., Soft Matter 8, 4427-4431 (2012). We report on the synthesis and characterization of multiresponsive hybrid microgel particles. The particles consist of ellipsoidal silica-coated maghemite cores subsequently coated with thermoresponsive poly (N-isopropylacrylamide) (PNIPAM) shells. The PNIPAM shell enables the hybrid particle to alter its size and ratio of long to small axis with increasing temperature while the core morphology remains unchanged. The maghemite core can be magnetically oriented along the long axis as evidenced by small-angle X-ray scattering (SAXS) and confocal microscopy. Dynamic light scattering techniques and confocal microscopy have been applied to study the particles' morphological evolution with increasing temperature in terms of their aspect ratio. The aspect ratio of the particles was found to vary from 1.25 to 1.45 within a temperature range from 20 °C to 44 °C.20. February 2012
