Epitaxial LaFeAsO1-xFx thin films grown by pulsed laser deposition

Superconducting and epitaxially grown LaFeAsO1-xFx thin films were successfully prepared on (001)-oriented LaAlO3 substrates using pulsed laser deposition. The prepared thin films show exclusively a single in-plane orientation with the epitaxial relation (001)[100]||(001)[100] and a full width at half-maximum value of 10. Furthermore, resistive measurement of the superconducting transition temperature revealed a Tc,90% of 25 K with a high residual resistive ratio of 6.8. The preparation technique applied, standard thin film pulsed laser deposition at room temperature in combination with a subsequent post-annealing process, is suitable for fabrication of high quality LaFeAsO1-xFx thin films. A high upper critical field of 76.2 T was evaluated for magnetic fields applied perpendicular to the c-axis and the anisotropy was calculated to be 3.3 assuming single band superconductivity. (rapid communication)