Chen Guangze, Rösner Malte, Lado Jose L
Department of Applied Physics, Aalto University, 02150 Espoo, Finland.
Institute for Molecules and Materials, Radboud University, NL-6525 AJ Nijmegen, The Netherlands.
J Phys Condens Matter. 2022 Oct 17;34(48). doi: 10.1088/1361-648X/ac9812.
Magnetic frustrations in two-dimensional materials provide a rich playground to engineer unconventional phenomena. However, despite intense efforts, a realization of tunable frustrated magnetic order in two-dimensional materials remains an open challenge. Here we propose Coulomb engineering as a versatile strategy to tailor magnetic ground states in layered materials. Using the frustrated van der Waals monolayer 1T-TaSas an example, we show how long-range Coulomb interactions renormalize the low energy nearly flat band structure, leading to a Heisenberg model which depends on the Coulomb interactions. Based on this, we show that superexchange couplings in the material can be precisely tailored by means of environmental dielectric screening, ultimately allowing to externally drive the material towards a tunable frustrated regime. Our results put forward Coulomb engineering as a powerful tool to manipulate magnetic properties of van der Waals materials.
二维材料中的磁阻挫为研究非常规现象提供了一个丰富的平台。然而，尽管付出了巨大努力，在二维材料中实现可调谐的阻挫磁序仍然是一个悬而未决的挑战。在此，我们提出库仑工程作为一种通用策略，用于调控层状材料中的磁基态。以阻挫范德华单层1T-TaS为例，我们展示了长程库仑相互作用如何重整化低能近平带结构，从而导出一个依赖于库仑相互作用的海森堡模型。基于此，我们表明材料中的超交换耦合可以通过环境介电屏蔽精确调控，最终能够从外部驱动材料进入可调谐的阻挫状态。我们的结果提出库仑工程是操纵范德华材料磁性质的有力工具。
