Superconducting transition width (ΔT_c) characteristics of 25 mol% Zr-added (Gd, Y)Ba₂Cu₃O_7−δsuperconductor tapes with high in-field critical current density at 30 K

Abstract

The superconducting transition width (∆Tc) characteristics of REBa2Cu3O7−δ (REBCO and RE = Gd, Y) superconductor tapes with Zr content of 25 mol% with high lift factor (ratio of critical current density (Jc) at 30 K, 3 T (B||c) to the Jc at 77 K, 0 T) has been determined. In this work, heavily doped (Gd, Y)Ba2Cu3O7−δ superconductor tapes with 25 mol% Zr addition were fabricated by metal organic chemical vapor deposition using a reel-to reel process. The optimal chemical composition range of (Gd, Y)Ba2Cu3O7−δ superconductor tapes with Zr content of 25 mol% to achieve critical current densities above 3.5 MA cm−2 at 77 K in zero applied magnetic field has been determined. A superconducting transition width (∆Tc) as narrow as 0.4 K and an onset critical transition temperature (Tc-onset) as high as 92 K were obtained in the 25 mol% Zr-added (Gd, Y)BaCuO superconductor tapes. Based on the mapped compositional phase diagram of the ∆Tc and lift factor, ∆Tc in the range of 0.7–0.9 K is observed in 25 mol% Zr-added (Gd, Y)BaCuO superconductor tapes with a high lift factor.

Effect of mixed pinning landscapes produced by 6 MeV oxygen irradiation on the resulting critical current densities Jc in 1.3 µm thick GdBa 2 Cu 3 O 7- d coated conductors grown by co-evaporation

“…During the last years, a great amount of effort has been orientated to improve the superconducting properties of RBa 2 Cu 3 O 7−δ (RBCO; R: Sm, Dy, Y, Gd) coated superconductors (CCs) [1,2,3,4]. One of the strongest aspects expected for applications such as motors and magnets is to be able to maintain high critical current density J c at high magnetic fields [5,6].…”

In-field critical current and pinning mechanisms at 4.2 K of Zr-added REBCO coated conductors

“…35 and 15% mol.% Zr-added (Gd,Y)BCO films was determined from the composition analysis by inductively coupled plasma mass spectroscopy (ICP-MS). (Ba + Zr)/Cu ratio has been previously shown to be strongly correlated with in-field critical current [16,25].…”

New insight into strain and composition of BaZrO3 nanorods in REBCO superconductor

“…The unit cell parameters depend on a number of factors including REBCO non-stoichiometry and Zr content [48,63]. For the samples evaluated in this study, we adopt the unit cell values of tetragonal (as-grown) REBCO and BZO as a = 3.86 and 4.16 Å, respectively, based on our estimates from 2D-XRD.…”

“…The striking effect of nanorods on flux pinning has sparked intense research on in-field performance optimization and mechanisms of self-assembly, including strain mismatch, growth kinetics and other aspects [5,15,[17][18][19][20][21][22][23]. The studies report widely varying nanorod landscapes, matching field, crystallographic texture, lattice parameters, critical temperature (T c ), self-field and in-field critical current (I c ), angular in-field I c dependence, size and density of nanorods, their angular splay distribution, and other relevant parameters [1,9,13,15,19,22,41,42,48,51,[61][62][63][64][65][66][67][68][69][70][71][72][73]. The level of improvement of in-field performance has been significant, with drastic increase in performance over a wide range of operating regimes, e.g.…”