2026-03-04 東京大学
局所的なレーザ照射によりトポロジカルα-Sn薄膜内に超伝導β-Snの微細精密パターンを形成
＜関連情報＞
- https://www.t.u-tokyo.ac.jp/press/pr2026-03-04-001
- https://advanced.onlinelibrary.wiley.com/doi/10.1002/adma.202512571
トポロジカルSn薄膜における超伝導ヘテロ構造の非破壊レーザーナノパターニング Non-Destructive Laser Nanopatterning of Superconducting Heterostructures in Topological Sn Thin Films
Le Duc Anh, Takahiro Saeki, Keita Ishihara, Daiki Nishigaki, Hideki Maki, Masaaki Tanaka
Advanced Materials Published: 24 January 2026
DOI:https://doi.org/10.1002/adma.202512571
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 (ξGL) 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.
