Neutron Mirror with Carbide Boron Unveils New Research Paths

Scientists from Sweden have developed a new way to create multilayer mirrors for neutrons by incorporating carbide boron into layers of iron and silicon. A study led by Anton Zubayer from the University of Lynchoping revealed that this modification enhances the reflectivity and polarization of neutron beams, especially at high scattering angles.

Neutron science involves investigating the scattering of slow neutrons from samples to determine their atomic structure and study dynamic and magnetic properties. Creating polarized neutron beams for certain experiments has been a challenge.

Conventionally, mirrors consisting of alternating layers of iron and silicon are used to polarize neutrons. However, the effectiveness of these mirrors diminishes at large scattering angles due to difficulties in creating smooth atomic boundaries between the layers. Additionally, using strong external magnetic fields to improve mirror efficiency is not always feasible as it can affect the samples being tested.

The new method proposed by Zubayer and his colleagues includes enriching the layers of iron and silicon with boron-11 enriched Bor-11. This innovation results in clearer layer boundaries and fewer imperfections, making the mirror more reflective and polarizing without the need for external magnetic fields. As a result, the mirror can be placed closer to the samples, improving the quality of experimental outcomes.

The improved features of the new mirror pave the way for more effective experiments using polarized neutron beams, potentially leading to new discoveries in physics, chemistry, biology, and medicine. The study has been published in the journal Science Advances.