Phase Vortex Lattices in Neutron Interferometry

Abstract

A combination of aluminium prisms inserted into a nested loop interferometer is used to generate a neutron phase vortex lattice with significant extrinsic orbital angular momentum, L_z=0.35, on a length scale of 220 microns, transverse to the propagation direction. Our method is a generalization of recently developed magnetic methods, such that we can exploit the strong nuclear interaction. The stronger potential of these prisms allows for the generation of a tighter lattice. Combined with recent advances in neutron compound optics and split crystal interferometry our method may be applied to the generation of intrinsic neutron orbital angular momentum states. Finally, we assert that, in its current state, our setup is directly applicable to anisotropic ultra small angle neutron scattering.