Nie Jin-Hua, Xie Tao, Chen Gang, Zhang Wenhao, Fu Ying-Shuang
School of Physics and Wuhan National High Magnetic Field Center, Huazhong University of Science and Technology, Wuhan 430074, China.
Nano Lett. 2023 Sep 13;23(17):8370-8377. doi: 10.1021/acs.nanolett.3c02772. Epub 2023 Sep 1.
Recent advances in creating moiré periods of two-dimensional heterostructures enable diverse and compatible tunability to modulate the conventional proximity effect involving superconductivity, magnetism, and topology. Here, by constructing a MnTe/NbSe heterojunction via molecular beam epitaxy growth, we report on a moiré-enhanced multiband superconductivity by low-temperature scanning tunneling microscopy/spectroscopy measurements. We observe a distinct double-gap superconducting spectrum on monolayer MnTe that is absent on the NbSe substrate. The subgap character exhibits a moiré-related oscillation in real space, which can be well described by an effective two-band model. The restored two-gap feature and its rapid suppression under a small magnetic field are speculated to be mediated by the moiré superlattice, which is closely related to the enhanced interband coupling strength of quasiparticle scattering. Our work paves the way for engineering proximitized properties of heterostructures by a moiré landscape with spatial modulations.
二维异质结构中莫尔周期的最新进展实现了多样且兼容的可调性，以调节涉及超导、磁性和拓扑的传统近邻效应。在此，通过分子束外延生长构建MnTe/NbSe异质结，我们通过低温扫描隧道显微镜/光谱测量报道了莫尔增强的多带超导性。我们在单层MnTe上观察到在NbSe衬底上不存在的独特双能隙超导光谱。能隙以下的特征在实空间中呈现出与莫尔相关的振荡，这可以用有效的双带模型很好地描述。恢复的双能隙特征及其在小磁场下的快速抑制被推测是由莫尔超晶格介导的，这与准粒子散射增强的带间耦合强度密切相关。我们的工作为通过具有空间调制的莫尔景观来设计异质结构的近邻化特性铺平了道路。
