We realize p-p′-p junctions in few-layer black phosphorus devices, and use magnetotransport measurements to study the equilibration and transmission of edge states at the interfaces of regions with different charge densities. We observe both full equilibration, where all edge channels equilibrate and are equally partitioned at the interfaces, and partial equilibration, where equilibration only takes place among modes of the same spin polarization. Furthermore, the inner p′ region with low-doping level in the junction can function as a filter for highly doped $p$ regions which demonstrates gate-tunable transmission of edge channels.

中文翻译：

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几层黑磷中量子霍尔边缘态的平衡和滤波

我们在几层黑磷器件中实现pp'-p结，并使用磁迁移测量研究了具有不同电荷密度的区域的界面处的边缘态的平衡和传输。我们既观察到完全平衡（其中所有边缘通道在界面处均等且均分），也观察到部分平衡（其中仅在相同自旋极化的模式之间发生平衡）。此外，在结中具有低掺杂水平的内部p'区域可以用作高掺杂的滤波器$p$ 演示边缘通道的门可调传输的区域。