论文标题
扭曲的WSE $ _2 $中的巨型非线性大厅效应
Giant nonlinear Hall effect in twisted WSe$_2$
论文作者
论文摘要
最近发现的一些非相互作用系统中发现的非线性霍尔效应（NHE）提供了一种新的机制，可以在时间反转对称条件下生成第二个谐波电气霍尔信号。在这里，我们通过使用扭曲的Moiré结构介绍了一种新的工程方法。我们发现，扭曲的WSE $ _2 $ BiLayer在将费米水平调整为Moiré平面乐队时展示了一个NHE。非线性大厅信号几乎对第一个莫伊尔频带进行了半填充，其发电效率至少比以前的实验大于两个数量级。我们建议巨型NHE和分化的产生效率源于质量分歧的连续莫特过渡，这是电阻率测量结果证明的。这项工作不仅展示了相互作用效应如何促进浆果曲率偶极子以产生新的量子现象，而且还表明了NHE测量值可以为开发一种研究量子关键的新工具提供的方法。
The recently discovered nonlinear Hall effect (NHE) in a few non-interacting systems provides a novel mechanism to generate second harmonic electrical Hall signals under time-reversal-symmetric conditions. Here, we introduce a new approach to engineering NHE by using twisted moiré structures. We find that the twisted WSe$_2$ bilayer exhibits a NHE when tuning the Fermi level to the moiré flat bands. Near half-filling of the first moiré band, the nonlinear Hall signal shows a sharp peak with the generation efficiency at least two orders of magnitude larger than those in previous experiments. We propose that the giant NHE and diverging generation efficiency originate from a mass-diverging type continuous Mott transition, which is evidenced by resistivity measurements. This work demonstrates not only how interaction effects can couple to Berry curvature dipoles to produce novel quantum phenomena, but also what NHE measurements can provide for developing a new tool to study the quantum criticality.
