Revealing the two-dimensional electronic structure and anisotropic superconductivity in a natural van der Waals superlattice (PbSe)$_{1.14}$NbSe$_2$

Autor: Zhong, Haoyuan, Zhang, Hongyun, Zhang, Haoxiong, Bao, Ting, Zhang, Kenan, Xu, Shengnan, Luo, Laipeng, Rousuli, Awabaikeli, Yao, Wei, Denlinger, Jonathan D., Huang, Yaobo, Wu, Yang, Xu, Yong, Duan, Wenhui, Zhou, Shuyun
Rok vydání: 2023
Předmět:
Zdroj: Phys. Rev. Mater. 7, L041801 (2023)
Druh dokumentu: Working Paper
DOI: 10.1103/PhysRevMaterials.7.L041801
Popis: Van der Waals superlattices are important for tailoring the electronic structures and properties of layered materials. Here we report the superconducting properties and electronic structure of a natural van der Waals superlattice (PbSe)$_{1.14}$NbSe$_2$. Anisotropic superconductivity with a transition temperature $T_c$ = 5.6 $\pm$ 0.1 K, which is higher than monolayer NbSe$_2$, is revealed by transport measurements on high-quality samples. Angle-resolved photoemission spectroscopy (ARPES) measurements reveal the two-dimensional electronic structure and a charge transfer of 0.43 electrons per NbSe$_2$ unit cell from the blocking PbSe layer. In addition, polarization-dependent ARPES measurements reveal a significant circular dichroism with opposite contrast at K and K' valleys, suggesting a significant spin-orbital coupling and distinct orbital angular momentum. Our work suggests natural van der Waals superlattice as an effective pathway for achieving intriguing properties distinct from both the bulk and monolayer samples.
Comment: 8 pages, 4 figures
Databáze: arXiv