Based on an effective k·p model, we form breathing Kagome bilayers with two different interlayer antiferroelectric (AFE) couplings, i.e., tail to tail and head to head, to study their magnetic and valley properties. Spin–orbit coupling and magnetic exchange interaction induce valley-layer locking when the bilayer is ferromagnetic, however, spin-layer locking appears for the case of antiferromagnetic states. The inequivalent interlayer antiferroelectric couplings correspond to different magnetic ground states, and the antiferroelectric states can be switched through the breathing process, so the ferroelectric, magnetic, and valley properties can be simultaneously modulated. Through first-principles calculations, we also predict a favorable breathing Kagome bilayer W3Br8, where the above coupling mechanism and tunable layer-locked valley Hall effects can be achieved. Our findings provide an applicable paradigm for achieving ferroelectric–magnetic–valley coupling in a single device, driving the development of next-generation electronic devices.

中文翻译：

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铁电-磁-谷耦合呼吸 Kagome 双层 W3Br8 中的可调层锁谷霍尔效应


基于有效的 k·p 模型，我们用两种不同的层间反铁电 （AFE） 耦合，即尾对尾和头对头形成呼吸 Kagome 双层，以研究它们的磁性和谷值。当双层为铁磁性时，自旋-轨道耦合和磁交换相互作用会引起谷层锁定，但是，在反铁磁状态的情况下会出现自旋层锁定。不等价的层间反铁电耦合对应于不同的磁基态，反铁电态可以通过呼吸过程进行切换，因此可以同时调制铁电、磁和谷性质。通过第一性原理计算，我们还预测了有利的呼吸 Kagome 双层 W3Br8，其中可以实现上述耦合机制和可调的层锁定谷霍尔效应。我们的研究结果为在单个器件中实现铁电-磁-谷耦合提供了一种适用的范例，从而推动了下一代电子器件的开发。