Tuning Jahn–Teller distortion and electron localization of LaMnO ₃ epitaxial films via substrate temperature

Abstract

Abstract High-quality epitaxial LaMnO 3 films have been grown on (001)-oriented LaAlO 3 substrates at different substrate temperatures by pulsed laser deposition. The layer-by-layer growth is indicated by oscillations of reflection high-energy electron diffraction. Raman spectra together with in-plane resistivity measurements reveal that the degree of Jahn–Teller (JT) distortion can be well controlled by the substrate temperature during film deposition. The JT distortion-related/induced electron localization is studied by fitting temperature-dependent resistivity with a three-dimensional variable range hopping model. It is found that the larger JT distortion leads to a stronger localization of electrons. This study might pave the way for further study of JT interaction and highly correlated electronic states in perovskites.