High-resolution neutron spectroscopy
Research report (imported) 2012 - Max Planck Institute for Solid State Research
The neutron spectrometer TRISP constructed by the MPI-FKF at the FRM II in Garching allows measurements of the lifetimes of lattice vibrations (phonons) and of spin excitations (magnons) in solids as a function of energy and momentum. The data generated by TRISP throw new light on several prominent problems in solid state physics. This article describes measurements of phonon lifetimes in the superconductors niobium and lead, and of magnon lifetimes in the antiferromagnet MnF2. In addition, the thermal expansion of MnSi was determined under extreme conditions by the Larmor-diffraction method.