Copper-based superconductors commonly have a CuO₂ plane structure, where high-temperature superconductivity occurs. Due to these characteristics, extensive research has been conducted on whether high-temperature superconductivity can occur even in a single layer of the CuO₂ plane. However, a pure CuO₂ plane single layer has not been achieved so far. In this study, we constructed a heterostructure system with a La_2–xSr_xCuO₄ (LSCO) monolayer containing a single CuO₂ plane and measured the resulting electronic structures. Monolayer LSCO has metallic and bulk-like electronic structures. Additionally, it was observed that the LSCO monolayer is significantly influenced by interfacial effects with neighboring layers. The results of this study provide a platform for the ideal two-dimensional copper-based superconductor research.

Authors: Youngdo Kim, Byeongjun Gil, Jinkwon Kim, Yeonjae Lee, Donghan Kim, Sungsoo Hahn, Tae Won Noh, Miyoung Kim, and Changyoung Kim*

Link: https://pubs.acs.org/doi/full/10.1021/acs.nanolett.3c00994