The effects of growth temperature onc-axis-correlated pinning centers in PLD-ErBa2Cu3O7−δfilms with Ba(Er0.5Nb0.5)O3

Effects of growth temperatures in epitaxial ErBa 2 Cu 3 O 7−δ films with one-dimensional nanorods were discussed from their microstructures and superconducting properties. c -axis-oriented BaNb 2 O 6 -doped ErBa 2 Cu 3 O 7−δ films were grown on (100)-oriented SrTiO 3 substrates grown at 710 and 760 °C by pulsed-laser deposition. Atomic force microscopy analysis showed that film surface steps on the three-dimensional islands increased with decreasing growth temperature ( T S ). Then, nanorod morphologies were also changed by T S . Ba(Er 0.5 Nb 0.5 )O 3 nanorods were observed clearly in transmission electron microscopy images of the films. The nanorods were thinner and denser at a lower T S under a nominal BaNb 2 O 6 (BNO) doping concentration. In the case of T S = 710 °C, the diameter and number density of nanorods with 1.5 wt%BNO doping were 4–6 nm and 2.6 × 10 11 cm −2 , respectively. Furthermore, the nanorods could effectively act as c -axis-correlated pinning centers in the film grown at a lower T S . Consequently, the pinning effects were controlled by nanorod morphologies through varying the T S .