Fabrication of Meter‐Long Class Fe(Se,Te)‐Coated Conductors with High Superconducting Performance

Previous research results have demonstrated that Fe(Se,Te) films with high critical current density Jc can be realized on flexible metal substrates and are promising for high field applications at 4.2 K. For practical applications, the length of the coated conductor is a key factor. Regarding the fabrication of long Fe(Se,Te)‐coated conductor tapes, the biggest difficulty is how to achieve a breakthrough from static coating to continuous dynamic coating process. Herein, it is demonstrated that Fe(Se,Te)‐coated conductor with high superconducting performance can be continuously fabricated. 1 m‐long Fe(Se,Te)‐coated conductors have been successfully fabricated by multiturn pulsed laser deposition on CeO2‐buffered ion beam‐assisted deposition MgO tape. The Fe(Se,Te)‐coated conductors have high critical temperature of 17.5 K and Jc over 2 MA cm−2 at 4.2 K and self‐field. The end‐to‐end critical current of 1 m‐long Fe(Se,Te)‐coated conductor is as high as 108 A cm−1‐width at 4.2 K and self‐field, and the corresponding Jc is 1.54 MA cm−2, which is above the threshold for industrial applications. The upper critical field at 0 K is deduced to be about 53 T. To the best of knowledge, this is the first demonstration of continuous fabrication of long Fe(Se,Te)‐coated conductors with high performance.