Room temperature ferromagnetism in the nanolaminated MAX phase (Mn_1−xCr_x)₂GaC

MAX phases are a class of intrinsically nanolaminated materials, which combine features of metals and ceramics, owing to the alternating metallic and covalent bonding between atomic layers. Magnetic MAX phases have been known for a decade, but ferromagnetism at room temperature in this highly anisotropic system has been elusive, limiting their value as magnets in practice. Here, we show that a MAX phase with a strong ferromagnetic response is obtained by substituting Mn with Cr on the M-site in the well-known Mn₂GaC. The ferromagnetic response is observed in ( M n 1 − x C r x ) 2 GaC with 0.06 < x < 0.29 up to temperatures well exceeding room temperature (489 K). The strongest magnetization is achieved with x = 0.12, reaching a saturation moment of 1.25 μ_B and a remanence of 0.67 μ_B per M-atom at 3 K and maintaining 0.90 and 0.44 μ_B per M-atom, respectively, at 300 K. This is the first experimental report of a significant ferromagnetic response in a MAX phase at room temperature. The results open the door to the use of MAX phases in a broad range of applications, from bulk magnets in power electronics to spintronic devices.