Non‐Destructive Laser Nanopatterning of Superconducting Heterostructures in Topological Sn Thin Films

Abstract

ABSTRACT Heterostructures composed of superconductors and topological materials have emerged as compelling platforms for realizing topological superconductivity and fault‐tolerant quantum computation. A critical bottleneck, however, lies in achieving atomically clean and structurally coherent interfaces between dissimilar materials. Here, we report the fabrication of high‐quality planar heterostructures composed of the topological Dirac semimetal (TDS) α‐Sn and the superconducting β‐Sn phase, achieved by focused laser irradiation on α‐Sn thin films. The irradiated regions undergo a phase transition from α‐Sn to β‐Sn, exhibiting atomically smooth surfaces with a root mean square (RMS) roughness of just 0.75 nm. The laser‐induced β‐Sn demonstrates superconductivity with a critical temperature of 3.7 K and a Ginzburg–Landau coherence length ( ξ GL ) of 68.2 nm. Notably, β‐Sn nanowires patterned through this method exhibit a pronounced superconducting diode effect, reaching a maximum rectification ratio ( η ) of 10.8%. These findings establish laser irradiation as a versatile, non‐destructive, and scalable approach for fabricating high‐quality α‐Sn/β‐Sn heterostructures, offering a promising route toward next‐generation superconducting quantum devices.