Field electron emission from large-area Y1Ba2Cu3O7-x superconducting films in vacuum

Thin films of Y₁Ba₂Cu₃O_7-x deposited on copper and stainless steel electrodes by a flame spray method were tested in vacuum at electric fields ranging from 10 to 100 kV/cm. Field electron emission current was measured from the surfaces before and after the application of the film. Metallic surfaces, of 20 cm² in surface, cooled to LN₂ (~90 K) temperatures showed a 1.75 to 2×increase in current. The coated surfaces showed a 5 to 6× increment in current when compared to room temperature metallic surfaces. Stainless steel electrodes with a surface area of 20 cm², which were coated by a flame spray process and tested under vacuum, showed a similar behavior. Coating procedures and experimental results are shown