标题： 二维BaNiCl$_3$中具有高反常霍尔电导的本征Chern半金属 显示英文标题

标题： Intrinsic Chern Half-Metal with High Anomalous Hall Conductivity in 2D BaNiCl$_3$

摘要： 二维（2D）半金属在费米能级处提供完全的自旋极化，使其成为无耗散自旋输运的候选材料。然而，具有稳健拓扑特性的本征二维半金属，特别是大陈数反常霍尔电导率的，仍然极为罕见。通过第一性原理计算，我们确定了原子级薄的BaNiCl$_3$，一种层状卤化物钙钛矿（钙钛烯），作为一种拓扑半金属。它表现出高的陈数（$C \ge 2$），大的反常霍尔电导率为316~$\Omega^{-1},\mathrm{cm}^{-1}$，以及费米速度为$\approx 0.78 \times 10^6$米/秒。完全自旋极化和高载流子速度的同时存在表明低耗散自旋输运。自旋轨道耦合打开了一个相当大的拓扑隙$\sim 20\,$毫电子伏，产生了非平凡的Berry曲率并增强了反常霍尔响应。铁磁性由Ni$^{2+}$（$d^8$）构型和氯介导的超交换稳定，支持在较高温度下的磁有序。 这些结果证实了 BaNiCl$_3$是一种罕见的本征 Chern 半金属，具有在量子技术和自旋电子技术中的潜在应用。 显示英文摘要

摘要： Two-dimensional (2D) half-metals offer complete spin polarization at the Fermi level, making them candidates for dissipationless spin transport. Yet intrinsic 2D half-metals exhibiting robust topological features, particularly large Chern number anomalous Hall conductivities, remain exceptionally rare. Using first-principles calculations, we identify atomically thin BaNiCl$_3$, a layered halide perovskite (perovskene), as a topological half-metal. It exhibits a high Chern number ($C \ge 2$), a large anomalous Hall conductivity of 316~$\Omega^{-1},\mathrm{cm}^{-1}$, and a Fermi velocity of $\approx 0.78 \times 10^6$ m/s. The coexistence of complete spin polarization and high carrier velocity suggests low-dissipation spin transport. Spin-orbit coupling opens a sizable topological gap of $\sim 20\,$ meV, yielding nontrivial Berry curvature and enhancing the anomalous Hall response. Ferromagnetism is stabilized by the Ni$^{2+}$ ($d^8$) configuration and Cl-mediated superexchange, supporting magnetic ordering at elevated temperatures. These results establish BaNiCl$_3$ as a rare intrinsic Chern half-metal, with potential applications in quantum and spintronic technologies.