2025/04/22 by Tei, Jushin, Mizushima, Takeshi, Fujimoto, Satoshi · 1 citation
#FOS: Physical sciences #Superconductivity (cond-mat.supr-con)
paper · doi:10.48550/arxiv.2504.16166
We propose the surface of topological superconductors as a platform for realizing two-dimensional flat bands, where electron interactions play a crucial role. The surface flat bands originate from topological features supported by two key mechanisms: (1) a trivial Chern number prevents the zero-energy states from merging into the continuum of the bulk spectrum, thereby ensuring their confinement within the superconducting gap; and (2) weak spin conservation allows the gap function to exhibit phase winding. As a consequence, the surface exhibits a remarkably high density of states at nearly zero energy. Such surface states are likely to be realized in the candidate topological superconductor UTe2. Our results provide important insights into the interpretation of recent Josephson STM experiments on UTe2.