Towards polarizing beam splitters for cold neutrons using superparamagnetic diffraction gratings

TL;DR

This paper explores the development of tunable polarizing beam splitters for cold neutrons using superparamagnetic diffraction gratings, which depend on magnetic field strength and neutron spin, enabling spin-selective reflection and transmission.

Contribution

It introduces a novel approach to create spin-dependent neutron beam splitters using superparamagnetic nanoparticle-polymer gratings with tunable diffraction properties.

Findings

Diffraction efficiency depends on magnetic field and neutron spin state.

Potential to create spin-selective mirrors for cold neutrons.

Feasibility of tunable neutron polarizing beam splitters.

Abstract

For holographic gratings recorded in superparamagnetic nanoparticle-polymer composites the diffraction efficiency should -- next to grating spacing, nanoparticle concentration and grating thickness -- depend on the strength of an external magnetic field and the incident neutron spin state. As a consequence, diffraction gratings should be tunable to act as mirrors for one spin state, while being essentially transparent for the other. Thus, polarizing beam splitters for cold neutrons become feasible.