On the Anderson-localization of ultra-cold neutrons

We investigate the process of weak and strong Anderson-localization of ultra-cold neutron (UCN) matter-waves in disordered mesoscopic systems. Contrary to the case of photon localization, in the approximation of independent scattering processes of ultracold neutrons, there is always a regime where the transport mean free path necessarily meets the Joffe–Regel criterion. However, this is not necessarily the case if multiple coherent scattering effects are taken into account. We report on a first experimental study and discuss the relevance of UCN localization to T-violation searches.