Realization of Air-Stable Two-Dimensional Superconductor Nb₂Pd₃Te₅ With Quasi-One-Dimensional Pair Density Modulation

Two-dimensional (2D) superconductors provide a fertile platform for exploring reduced-dimensional superconductivity and emergent quantum phenomena. Incorporating quasi-one-dimensional (quasi-1D) structural motifs into 2D superconductors offers a powerful route to engineer strong electronic anisotropy, enabling unconventional superconducting states and anisotropic superconducting transport functionalities. However, such systems remain rarely realized. Here we report the realization of a 2D superconductor Nb₂Pd₃Te₅, exhibiting an intrinsic quasi-1D pair density modulation. Monolayer and bilayer Nb₂Pd₃Te₅ is synthesized via van-der-Waals epitaxy. Using ultralow-temperature scanning tunneling microscopy/spectroscopy, we observe the quasi-1D crystal structure and superconductivity below ∼0.6 K with a pronounced quasi-1D pair density modulation. Remarkably, both monolayer and bilayer Nb₂Pd₃Te₅ show strong air stability. Our findings establish atomically 2D Nb₂Pd₃Te₅ as a robust and promising platform for exploring novel low-dimensional quantum phenomena and anisotropy-enabled superconducting devices.