J. Phys. D: Appl. Phys. 50, 43LT02 (2017)
H. Wei, Ch.Yang, J. Barzola-Quiquia, M. Welke, R. Denecke, Chr. Patzig, Th. Höche, P. Esquinazi, M. Grundmann, and M. Lorenz
Abstract
High-quality epitaxial LaMnO3/LaAlO3 superlattices (SLs) with (0 0 1), (0 1 1), and (1 1 1) out-of-plane orientation were grown by pulsed laser deposition. This SL material was predicted theoretically as a Chern insulator for realizing the quantum anomalous Hall effect. In our investigations, a paramagnetic-ferromagnetic phase transition is found with decreasing temperature around 100 K, indicating a controllable ferroic order at low temperatures. Electrical transport measurements reveal a thermally activated single-gap behavior with a fitted band gap of 436 meV for the (1 1 1)-oriented SL. With that, the results prove the predictions of a ferromagnetic background in the SLs, and of a gapped band structure.