Abstract We investigated the ground state of monolayer 1T-XCl2 (X: Fe, Co, and Ni) using the generalized Bloch theorem, which can generate ferromagnetic, spiral, and antiferromagnetic states. Each state was represented by a unique spiral vector that arranges the magnetic moment of magnetic atom in the primitive unit cell. We found the ferromagnetic ground state for the FeCl2 and NiCl2 while the spiral ground state appears for the CoCl2. We also showed that the ground state depends sensitively on the lattice constant. When the hole–electron doping was taken into account, we found the phase transition, which involves the ferromagnetic, spiral, and antiferromagnetic states, for all the systems. Since the spin–spin interaction in the monolayer metal dichlorides is influenced by the competition between the direct exchange and the superexchange, we justify that the carrier concentration determines which interaction should dominate.

中文翻译：

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金属二氯化物 XCl2（X：Fe、Co 和 Ni）中的载流子诱导相变

摘要 我们使用广义布洛赫定理研究了单层 1T-XCl2（X：Fe、Co 和 Ni）的基态，该定理可以产生铁磁、螺旋和反铁磁状态。每个状态都由一个独特的螺旋矢量表示，该矢量在原始晶胞中排列磁性原子的磁矩。我们发现 FeCl2 和 NiCl2 为铁磁基态，而 CoCl2 为螺旋基态。我们还表明基态敏感地取决于晶格常数。当考虑空穴-电子掺杂时，我们发现了所有系统的相变，包括铁磁、螺旋和反铁磁状态。由于单层金属二氯化物中的自旋-自旋相互作用受直接交换和超交换之间的竞争影响，