Stability Test of OAM Generating Neutron Optics

Particles such as neutrons can often be better described by spread out waves than by point like particles in quantum mechanics. In the simplest case the wavefronts of these quantum mechanical waves are parallel. Orbital angular momentum (OAM) refers to a special structure imprinted on these waves which results in helical wavefronts. These twisted waves have been observed in acoustics, optics and electrons. In neutron physics claims of twisted wavefronts are still controversial, due to the difficulty in resolving this small structure. We have derived a method by which OAM can be imprinted on the neutron using an electric field. Nonetheless the amount of OAM generated by this method is small. Therefore we propose to determine the stability and sensitivity of the Larmor instrument down to 10^-5 radians, which would be required to effectively measure OAM generation in electric fields.