ABSTRACT
Muon spin rotation (μSR) is a particularly useful technique with which to study super-conductors, particularly the mixed state. As a microscopic probe it can obtain structural information not accessible to macroscopic methods such as magnetisation measurements. While to date the use of muons to study superconductors has been almost exclusively confined to the mixed state, recent advances in the production of ultra low momentum muons could make possible the investigation of superconductivity at surfaces and interfaces in the Meissner state. The chapter is concerned with the more usual investigation of the mixed state. A study on single crystals of the anisotropic conventional superconductor NbSe2 has been carried out to investigate the magnetic field dependence of the vortex-core radius and penetration depth. The resulting electromagnetic interactions between flux lines will also be anisotropic, so in general the flux line lattice will be a distorted hexagonal or distorted square arrangement.
