A New Highly Anisotropic Rh‐Based Heusler Compound for Magnetic Recording

Abstract

The development of high‐density magnetic recording media is limited by superparamagnetism in very small ferromagnetic crystals. Hard magnetic materials with strong perpendicular anisotropy offer stability and high recording density. To overcome the difficulty of writing media with a large coercivity, heat‐assisted magnetic recording was developed, rapidly heating the media to the Curie temperature Tc before writing, followed by rapid cooling. Requirements are a suitable Tc, coupled with anisotropic thermal conductivity and hard magnetic properties. Here, Rh2CoSb is introduced as a new hard magnet with potential for thin‐film magnetic recording. A magnetocrystalline anisotropy of 3.6 MJ m−3 is combined with a saturation magnetization of μ0Ms = 0.52 T at 2 K (2.2 MJ m−3 and 0.44 T at room temperature). The magnetic hardness parameter of 3.7 at room temperature is the highest observed for any rare‐earth‐free hard magnet. The anisotropy is related to an unquenched orbital moment of 0.42 μB on Co, which is hybridized with neighboring Rh atoms with a large spin–orbit interaction. Moreover, the pronounced temperature dependence of the anisotropy that follows from its Tc of 450 K, together with a thermal conductivity of 20 W m−1 K−1, make Rh2CoSb a candidate for the development of heat‐assisted writing with a recording density in excess of 10 Tb in.−2.

Antiskyrmions and their electrical footprint in crystalline mesoscale structures

“…Our studies of transport, magnetization and ferromagnetic resonance reveal a semi-hard-magnetic phase, and hence the unique link of ASKs to anisotropies, not possible in the cubic B20 compounds with weak anisotropy. We find this hard magnetic phase to increase as we reduce the thickness of the sample, which is particularly interesting for scalable electronic devices [47][48][49]. Many hard magnetic materials are strongly susceptible to finite sizes and may display nontrivial magnetic textures detectable by Hall transport [29,50].…”

Antiskyrmions and their electrical footprint in crystalline mesoscale structures

“…Our studies of transport, magnetization and ferromagnetic resonance reveal a semi-hard-magnetic phase, and hence the unique link of ASKs to anisotropies, not possible in the cubic B20 compounds with weak anisotropy. We find this hard magnetic phase to increase as we reduce the thickness of the sample, which is particularly interesting for scalable electronic devices [47][48][49]. Many hard magnetic materials are strongly susceptible to finite sizes and may display nontrivial magnetic textures detectable by Hall transport [29,50].…”

Giant Thermoelectric Power Factor Anisotropy in PtSb1.4Sn0.6

“…Element analysis was performed using energy-dispersive X-ray spectroscopy (EDS) in a JEOL LSM-6500 scanning electron microscope. The chemical composition determined by the SEM-EDS gives Pt:Sb:Sn = 32(1):46(2):22 (2). Single-crystal XRD data were collected on a crystal mounted on a low-background plastic holder using Paratone-N oil under a cold stream of nitrogen gas.…”