Reflective, polarizing, and magnetically soft amorphous neutron optics with B-enriched BC.

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 BC into Fe/Si multilayers, amorphization and smooth interfaces can be achieved, yielding higher neutron reflectivity, less diffuse scattering, and higher polarization.

Controlling metal-insulator transitions in reactively sputtered vanadium sesquioxide thin films through structure and stoichiometry.

We present a study of [Formula: see text] thin films grown on c-plane [Formula: see text] substrates by reactive dc-magnetron sputtering. Our results reveal three distinct types of films displaying different metal-insulator transitions dependent on the growth conditions. We observe a clear temperature window, spanning 200 [Formula: see text]C, where highly epitaxial films of [Formula: see text] can be obtained wherein the transition can be tuned by controlling the amount of interstitial oxygen in the films through the deposition conditions.

The impact of number of repeats N on the interlayer exchange in [Formula: see text](001) superlattices.

The strength of the interlayer exchange coupling in [Fe/MgO][Formula: see text](001) superlattices with 2 ≤ N ≤ 10 depends on the number of bilayer repeats (N). The exchange coupling is antiferromagnetic for all the investigated thicknesses while being nine times larger in a sample with N = 4 as compared to N = 2. The sequence of the magnetic switching in two of the samples (N = 4, N = 8) is determined using polarized neutron reflectometry.

Large uniaxial magnetostriction with sign inversion at the first order phase transition in the nanolaminated MnGaC MAX phase.

In 2013, a new class of inherently nanolaminated magnetic materials, the so called magnetic MAX phases, was discovered. Following predictive material stability calculations, the hexagonal MnGaC compound was synthesized as hetero-epitaxial films containing Mn as the exclusive M-element. Recent theoretical and experimental studies suggested a high magnetic ordering temperature and non-collinear antiferromagnetic (AFM) spin states as a result of competitive ferromagnetic and antiferromagnetic exchange interactions.

Tailoring magnetism at the nanometer scale in SmCo5 amorphous films.

The thickness dependence of magnetic properties has been studied in SmCo5 amorphous films with imprinted in-plane anisotropy for thicknesses ranging down to the nanometer scale (2.5-100 nm). The field induced in-plane magnetic anisotropy decreases considerably when the film thickness is below 20 nm.