Crystal structures and magnetic properties of Fe_1.93-xCo_xP_1-ySi_y compounds

In view of the interest that (Fe,Co)₂(P,Si) compounds have as potential permanent magnets, their structural and magnetic phase diagrams are explored focusing on establishing the range where the hexagonal Fe₂P-type structure is observed. In Fe_1.93-xCo_xP_1-ySi_y, the highest Si...

(Fe,Co)₂(P,Si) rare-earth free permanent magnets: From macroscopic single crystals to submicron-sized particles

While rare-earth magnets exhibit unchallenged hard-magnetic properties, looking for alternatives based on inexpensive elements of non-critical supply remains of utmost interest. Here, we demonstrate that (Fe,Co)₂(P,Si) single crystals combine a large magnetocrystalline anisotropy (K₁ ≈ 0.9 MJ m⁻³ at 300 K),...

Lattice dynamics across the magnetic transition in (Mn,Fe)1.95(P,Si)

The lattice dynamics in MnFe0.95Si0.50P0.50 were investigated experimentally using Fe57 nuclear inelastic scattering and inelastic x-ray scattering across the first-order magnetic transition which occurs close to room temperature. The lattice dynamics characterization was supported by a macroscopic magnetic characterization, an x-ray...

Effect of Carbon Doping on the Structure and Magnetic Phase Transition in (Mn,Fe₂(P,Si))

Given the potential applications of (Mn,Fe₂(P,Si))-based materials for room-temperature magnetic refrigeration, several research groups have carried out fundamental studies aimed at understanding the role of the magneto-elastic coupling in the first-order magnetic transition and further optimizing this system. Inspired by the...

Efficient Room-Temperature Cooling with Magnets

Magnetic cooling is a highly efficient refrigeration technique with the potential to replace the traditional vapor compression cycle. It is based on the magnetocaloric effect, which is associated with the temperature change of a material when placed in a magnetic field. We present experimental evidence for the origin of the giant entropy...