Fe–Te–Se epitaxial thin films with enhanced superconducting properties

Abstract

Epitaxial Fe–Te–Se thin films were deposited by pulsed laser deposition at 250–600 °C on SrTiO3 (100), MgO (100), LaAlO3 (100) and CaF2 (100) single crystal substrates. The best superconducting film was grown on CaF2: K and K with Tdep = 300 °C and 3 Hz. Critical current density Jc (T = 4.2 K) was 0.41 × 106 A cm−2 at 0 T and 0.23 × 106 A cm−2 at 9 T. The angular dependence of Jc shows a broad c-axis correlated peak when B ≥ 3 T.