Wang J.,Ou X. L.,Zhang J.,Chen X. Y.,Zhao K.,Yang X. S.,Zhao Y.
Fe(Te,Se) is a simple, iron-based compound that is conducive to the study of superconductivity mechanisms and has potential for large-scale applications. At present, Fe(Te,Se) thin films are primarily prepared using the pulsed laser deposition method. Herein, FeTe 0.6 Se 0.4 films were grown by magnetron sputtering on CaF 2 substrates. The effect of sputtering pressure on the superconductivity of the film was investigated. Excessive pressure caused a higher iron content, which affected the superconductivity and prevented it from completely reaching a zero-resistance state. Δ T c was smaller for the film grown under 0.2 Pa, and its upper critical field reached 144.35 T, which indicates its greater application potential. Our results illustrated that sputtering pressure was a critical process parameter, which provided an important reference for future research to fabricate commercial iron-based superconducting tapes by magnetron sputtering.
Qingshuang Ma,Feng Lan,Xinhua Li,Zunfeng Du,Huijun Li,Zongqing Ma
In this work, the superconducting properties of FeSe 1−x S x with 0 ≤ x ≤ 0.5 were studied. With S doping, T c is enhanced and shows a dome shape in the studied composition range. XRD measurements demonstrate that S substituting Se sites introduces positive chemical pressure, which can suppress the orbital ordering, manifesting as the decrease of T s . Hall measurements demonstrate that S doping can effectively tune the charge carriers and make hole-type carriers predominant. However, no maxing T c is obtained as T s vanishes in FeSe 0.7 S 0.3 , indicating the nematic order has no universal influence on the superconductivity of FeSe system.