より優れた中性子ミラーは物質の内部の秘密を明らかにできる(Better neutron mirrors can reveal the inner secrets of matter)

2024-02-29 リンショーピング大学

＜関連情報＞

• https://liu.se/en/news-item/battre-neutronspeglar-kan-avsloja-materiens-inre-hemligheter
• https://www.science.org/doi/10.1126/sciadv.adl0402

11B濃縮B4Cを用いた反射、偏光、磁気的に柔らかいアモルファス中性子オプティクス Reflective, polarizing, and magnetically soft amorphous neutron optics with 11B-enriched B4C

ANTON ZUBAYER , NAUREEN GHAFOOR , KRISTBJÖRG ANNA THÓRARINSDÓTTIR , SJOERD STENDAHL , […], AND FREDRIK ERIKSSON
Science Advances  Published:14 Feb 2024
DOI:https://doi.org/10.1126/sciadv.adl0402

Abstract

The utilization of polarized neutrons is of great importance in scientific disciplines spanning materials science, physics, biology, and chemistry. However, state-of-the-art multilayer polarizing neutron optics have limitations, particularly low specular reflectivity and polarization at higher scattering vectors/angles, and the requirement of high external magnetic fields to saturate the polarizer magnetization. Here, we show that, by incorporating ¹¹B₄C into Fe/Si multilayers, amorphization and smooth interfaces can be achieved, yielding higher neutron reflectivity, less diffuse scattering, and higher polarization. Magnetic coercivity is eliminated, and magnetic saturation can be reached at low external fields (>2 militesla). This approach offers prospects for substantial improvement in polarizing neutron optics with nonintrusive positioning of the polarizer, enhanced flux, increased data accuracy, and further polarizing/analyzing methods at neutron scattering facilities.