Reversible critical current performance of FeSe_0.5Te_0.5 coated conductor tapes under uniaxial tensile strain

Abstract

FeSe0.5Te0.5 coated conductor as a kind of 11-type iron-based superconductor is currently attracting much attention. Recently, the bare FeSe0.5Te0.5 coated conductor tapes were developed by Shanghai Jiao Tong university and verified their superconductivity. For the future application, the FeSe0.5Te0.5 tapes should be subjected to the high electromagnetic forces and stress-strain. In this study, the authors encapsulated the bare FeSe0.5Te0.5 coated conductor tapes with copper layers to enhance the mechanical performance. The reversible critical current performance of the bare and the copper encapsulated FeSe0.5Te0.5 tapes under uniaxial tensile strain was tested. The critical currents of two kinds of tapes were measured over a wide range of applied uniaxial tensile strain by the U-shaped bending spring, respectively. The results show the critical performance of the bare FeSe0.5Te0.5 tapes decreases linearly with respect to tensile strain. The copper encapsulated FeSe0.5Te0.5 tapes have better performance than the bare tapes, with an irreversible tensile strain limit of 0.15%. In addition, the actual irreversible tensile strain limit of the copper encapsulated FeSe0.5Te0.5 tapes reaches 0.29% after considering the influence of the cooling process.

First performance test of FeSe0.5Te0.5 coated conductor coil under high magnetic fields

“…The silver layer easily partially separates from the superconducting layer, damaging the superconductivity of the tape. In order to strengthen the mechanical properties of the FeSe 0.5 Te 0.5 tape, the FeSe 0.5 Te 0.5 tape was encapsulated at the Institute of Plasma Physics, Chinese Academy of Sciences (ASIPP) [21]. In this study, the strengthened FeSe 0.5 Te 0.5 encapsulated tape is 10.5 mm in width and 0.15 mm in thickness.…”

Critical Role Played by Interface Engineering in Weakening Thickness Dependence of Superconducting and Structural Properties of FeSe0.5Te0.5-Coated Conductors

“…Meanwhile, the J c is higher than 1 MA/cm 2 in self-field and still 0.1 MA/cm 2 in fields as high as 30 T, demonstrating their enormous potential for high-field applications. A recent research study by Liu et al has shown that the irreversible tensile strain limit of FST CCs is 0.29%, making them quite attractive for magnet applications.…”

“…Meanwhile, the J c is higher than 1 MA/cm 2 in self-field and still 0.1 MA/cm 2 in fields as high as 30 T, 16 demonstrating their enormous potential for high-field applications. A recent research study by Liu et al has shown that the irreversible tensile strain limit of FST CCs is 0.29%, 25 making them quite attractive for magnet applications. Currently, most studies on IBS CCs have been conducted with a superconducting layer below a few hundred nanometers, 26 yielding a low critical current I c or engineering critical current density J e , which are more important practical parameters for applications such as magnets, despite a high J c .…”

Hydrothermally Obtaining Superconductor Single Crystal of FeSe0.2Te0.8 without Interstitial Fe

“…The iron chalcogenide FeSe1−𝑥Te𝑥 superconductor [1] is regarded as a candidate for studying topological superconductivity [2][3][4][5] and is also promising in practical applications. [6][7][8] It is essential to synthesize high-quality FeSe1−𝑥Te𝑥 single crystals with bulk superconductivity for investigating the intrinsic physical properties. [9][10][11][12][13][14][15][16] The as-grown Fe 1+𝛿 Se1−𝑥Te𝑥 single crystals with the self-flux method inherently contains excess Fe atoms (𝛿 in quantity) for Te substitution 𝑥 > 0.5, which occupy the interstitial sites of the Fe(Se,Te) layers.…”