  The vortex matter in bulk type-II superconductors serves as a prototype
system for studying the random pinning problem in condensed matter physics.
Since the vortex lattice is embedded in an atomic lattice, small angle neutron
scattering (SANS) is the only technique that allows for direct structural
studies. In traditional SANS methods, the scattering intensity is a measure of
the structure factor averaged over the entire sample. Recent studies in vortex
physics have shown that it is highly desirable to develop a SANS technique
which is capable of resolving the spatial inhomogeneities in the bulk vortex
state. Here we report a novel slicing neutron diffraction technique using
atypical collimation and an areal detector which allows for observing the three
dimensional (3D) disorder of the vortex matter inside an as-grown Nb single
crystal.
