Zhang Honghai, Lou Yaya, Wu Dongni, Liao Yangfang, Xie Jing
College of Physics and Electronic Science, Guizhou Normal University, Guiyang 550001, China.
Phys Chem Chem Phys. 2024 Apr 24;26(16):12681-12697. doi: 10.1039/d3cp06033k.
The intrinsic ferromagnetism of two-dimensional transition metal carbide CoC is remarkable. However, its practical application in spintronic devices is encumbered by a low Curie temperature (). To surmount this constraint, double transition-metal carbide CoMC (M = Ti, V, Cr, Mn, Fe, Ni) monolayers are constructed with the aim of improving the magnetic properties and Curie temperature of CoC. The magnetic properties of CoMC monolayers are comprehensively investigated by first-principles calculations and the effects of hole doping and biaxial strain on the magnetic properties of CoMC (M = V, Cr, Mn) monolayers are also studied. The ground states of CoTiC, CoMnC and CoNiC monolayers all favor ferromagnetic ordering, whereas the CoVC and CoCrC monolayers favor antiferromagnetic ordering and the CoFeC monolayer is non-magnetic. Excitedly, the CoMnC monolayer displays a high total magnetic moment of 4.024 and a of 1366 K. Moreover, the control of hole doping can effectively improve the of CoVC, CoCrC, and CoMnC monolayers to 680, 1317, 3044 K, respectively. Finally, applying the in-plain biaxial strain, the CoVC monolayer can be transformed into a ferromagnetic semiconductor under a tensile strain of 6%. The values of CoVC, CoCrC, and CoMnC monolayers are tuned by biaxial strain to 440, 1334 and 2390 K, respectively. Their above room temperature demonstrates that these monolayers have potential applications in spintronic devices. These theoretical investigations provide valuable insights into guiding experimental synthesis endeavors.
二维过渡金属碳化物CoC的本征铁磁性十分显著。然而，其在自旋电子器件中的实际应用受到低居里温度（）的限制。为克服这一限制，构建了双过渡金属碳化物CoMC（M = Ti、V、Cr、Mn、Fe、Ni）单层，旨在改善CoC的磁性能和居里温度。通过第一性原理计算全面研究了CoMC单层的磁性能，还研究了空穴掺杂和双轴应变对CoMC（M = V、Cr、Mn）单层磁性能的影响。CoTiC、CoMnC和CoNiC单层的基态均有利于铁磁有序排列，而CoVC和CoCrC单层有利于反铁磁有序排列，CoFeC单层是非磁性的。令人兴奋的是，CoMnC单层表现出4.024的高总磁矩和1366 K的居里温度。此外，空穴掺杂的控制可有效将CoVC、CoCrC和CoMnC单层的居里温度分别提高到680、1317、3044 K。最后，施加面内双轴应变，CoVC单层在6%的拉伸应变下可转变为铁磁半导体。CoVC、CoCrC和CoMnC单层的居里温度通过双轴应变分别调至440、1334和2390 K。它们在室温以上的居里温度表明这些单层在自旋电子器件中具有潜在应用。这些理论研究为指导实验合成工作提供了有价值的见解。
