Structural and electrical properties of lanthanum copper oxide epitaxial thin films with different domain morphologies†
Abstract
Herein, we investigated the domain morphologies of defect-perovskite LaCuOx (2.5 ≤ x ≤ 3.0) thin films grown on cubic SrTiO3 (100) and orthorhombic NdGaO3 (110) substrates by pulsed-laser deposition. Both films were composed of narrow rectangular-shaped domains, which extended in the [001] direction of LaCuOx. The LaCuOx film grown on SrTiO3 showed a labyrinth-like domain pattern composed of 90° domains, whereas the film on NdGaO3 displayed a stripe pattern with 180° domains. Furthermore, we observed anisotropy in the resistivity; the resistivity along the length of the domains was about three times lower than that across their width. This indicated that the domain boundaries behaved as carrier scattering centers.