Canted Magnetic Structure and Topological Hall Effect in CoFeCrGa Heusler Alloy Thin Film

Heusler alloys provide an exceptional materials platform for exploring emergent spintronic and topological phenomena, owing to their highly tunable electronic and magnetic degrees of freedom [1-4]. We report on the growth and magnetic characterization of CoFeCrGa quaternary Heusler alloy thin films (~50 nm) deposited on Si/SiO₂ substrates via magnetron sputtering and subsequently ex situ annealed at 550 °C to promote chemical ordering. Room-temperature polarized neutron reflectometry reveals a canted magnetic structure, evidencing non-collinear spin alignment and the coexistence of competing magnetic interactions within the film. Magneto transport measurements display an asymmetric field dependence in the resistivity, consistent with spin-valve–like magnetoresistance driven by spin-dependent scattering across domain interfaces. Remarkably, an additional Hall resistivity component emerges below 1 Tesla, signifying a topological Hall effect originating from real-space Berry curvature associated with the canted spin texture. These findings demonstrate that CoFeCrGa combines complex magnetic ordering with non-trivial topological transport behavior, positioning it as a compelling candidate for next-generation spintronic and topological devices.