Mirrors for slow neutrons from holographic nanoparticle-polymer free-standing film-gratings

TL;DR

This paper demonstrates the creation of holographically arranged nanoparticle-polymer gratings in thin free-standing films that act as mirrors for slow neutrons, achieving high reflectivity without container-related scattering.

Contribution

It introduces a novel method for fabricating high-quality, free-standing neutron mirror gratings using holography in nanoparticle-polymer composites.

Findings

Achieved about 90% neutron reflectivity at 4.1 nm wavelength.

Produced 2 cm diameter, flexible, free-standing neutron mirrors.

Demonstrated high optical quality in nanoparticle-polymer gratings.

Abstract

We report on successful tests of holographically arranged grating-structures in nanoparticle-polymer composites in the form of 100 microns thin free-standing films, i.e. without sample containers or covers that could cause unwanted absorption/incoherent scattering of very-cold neutrons. Despite their large diameter of 2 cm, the flexible materials are of high optical quality and yield mirror-like reflectivity of about 90% for neutrons of 4.1 nm wavelength.