Theory of Moiré Magnetism in Twisted Bilayer α-RuCl 3
Theory of Moiré Magnetism in Twisted Bilayer α-RuCl 3
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扭曲双层 α-RuCl 3 中的莫尔磁性理论
DOI：
10.1021/acs.nanolett.3c04084
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发表时间：
2024
期刊：
影响因子：
10.8
通讯作者：
Erten, Onur
中科院分区：
文献类型：
--
作者：
Akram, Muhammad;Kapeghian, Jesse;Das, Jyotirish;Valentí, Roser;Botana, Antia S.;Erten, Onur
基于货车德瓦耳斯磁体的莫尔超晶格的最新发展和对α-RuCl 3磁相互作用的控制，本文提出了一个关于扭曲双层α-RuCl 3长程有序磁相的综合理论。使用第一性原理计算和原子模拟相结合，我们表明，堆叠相关的层间交换引起的阵列的磁相，可以通过控制扭转角来实现。特别是，我们发现了一个复杂的六边形域结构，其中多个锯齿状订单共存。这种多畴有序使层间能量最小化，同时承受由于畴壁形成而导致的能量成本。此外，我们表明，量子涨落可以增强整个相变。我们的研究结果表明，由于叠层依赖的层间交换在莫尔超晶格中的磁阻挫可以用来调谐量子涨落和α-RuCl 3的磁基态。
Motivated by the recent developments in moiré superlattices of van der Waals magnets and the desire to control the magnetic interactions of α-RuCl3, here we present a comprehensive theory of the long-range ordered magnetic phases of twisted bilayer α-RuCl3. Using a combination of first-principles calculations and atomistic simulations, we show that the stacking-dependent interlayer exchange gives rise to an array of magnetic phases that can be realized by controlling the twist angle. In particular, we discover a complex hexagonal domain structure in which multiple zigzag orders coexist. This multidomain order minimizes the interlayer energy while enduring the energy cost due to domain wall formation. Further, we show that quantum fluctuations can be enhanced across the phase transitions. Our results indicate that magnetic frustration due to stacking-dependent interlayer exchange in moiré superlattices can be exploited to tune quantum fluctuations and the magnetic ground state of α-RuCl3.