Efectos Hall, Nernst y Spin Hall anómalos en CoMnCrGa: Un estudio de primeros principios

The quaternary Heusler compound CoMnCrGa emerges as a highly promising candidate for spintronic and transverse thermoelectric applications, as revealed by comprehensive first-principles calculations. CoMnCrGa stabilizes in the Type-I cubic structure ($F\bar{4}3m$) with a ferromagnetic ground state. The total magnetic moment of $\sim 1.09\,\mu_B$ obeys the Slater-Pauling rule, indicating a nearly half-metallic character corroborated by high electronic spin polarization. Prominent Berry curvature hotspots near the Fermi level generate substantial anomalous transport responses, including an anomalous Hall conductivity of $\sim -325.7$~S/cm at $-158.8$~meV and an anomalous Nernst conductivity (ANC) of $\sim -0.828$~A/m-K at $-55.6$~meV at room temperature for the intrinsic compound ($\mu = 0$). The material also exhibits a remarkably large spin Hall conductivity of $\sim 128~(\hbar/e)$~(S/cm) at 198.8~meV, driven by strong spin-orbit coupling and localized spin Berry curvature. Notably, the ANC demonstrates exceptional tunability and thermal stability, reaching $\sim 0.75$~A/m-K at room temperature under optimal electron doping ($\mu = 0.3$~eV). The coexistence of robust ferromagnetism, high spin polarization, large spin Hall conductivity, and tunable anomalous Nernst effect positions CoMnCrGa as a premier material for next-generation spintronic and spin-caloritronic devices.