Open AccessIncrease in the infield critical current density of MgB2 thin films by high-temperature post-annealing
Author(s) -
Hiroto Kambe,
Iwao Kawayama,
Naoya Kitamura,
Ataru Ichinose,
Takumu Iwanaka,
Toshiaki Kusunoki,
Toshiya Doi
Publication year - 2021
Publication title -
applied physics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.911
H-Index - 94
eISSN - 1882-0786
pISSN - 1882-0778
DOI - 10.35848/1882-0786/abdac3
Subject(s) - annealing (glass) , critical current , materials science , fabrication , thin film , condensed matter physics , current density , analytical chemistry (journal) , nanotechnology , superconductivity , composite material , chemistry , physics , medicine , alternative medicine , pathology , quantum mechanics , chromatography
We propose a novel fabrication technique based on the formation of a Nb protective layer on a MgB 2 thin film and high-temperature post-annealing to increase the critical current density ( J c ) of MgB 2 films under an external magnetic field. Analyses of the crystal structure and the composition of the processed MgB 2 films confirmed the suppression of the evaporation and oxidation of Mg by high-temperature annealing above 550 °C. The MgB 2 film annealed at 650 °C exhibited a J c of 1.62 MA cm −2 under 5 T, which is the highest reported value for MgB 2 films, wires, and bulk samples to date.