For ultracold neutrons with a kinetic energy below 10 neV, strong scattering, characterized by 2πlc/λ≤1, can be obtained in metamaterials of C and 7Li. Here lc and λ are the coherent scattering mean free path and the neutron wavelength, respectively. UCN interferometry and high-resolution spectroscopy (nano-electronvolt to pico-electronvolt resolution) in parallel waveguide arrays of neutronic metamaterials are given as examples of new experimental possibilities.
@article{arxiv.2009.07900,
title = {Strong scattering and parallel guiding of ultracold neutrons},
author = {Zhehui Wang and Marcel Demarteau and C. L. Morris and Yanhua Shih},
journal= {arXiv preprint arXiv:2009.07900},
year = {2020}
}