Structural investigation of (111) oriented (BiFeO3)((1-x)Lambda)/(LaFeO3)(x Lambda) superlattices by X-ray diffraction and Raman spectroscopy

J. Belhadi (1) , S. Yousfi (2) , H. Bouyanfif (1) , M. El Marssi (1)

1 LPMC - Laboratoire de Physique de la Matière Condensée - UR UPJV 2081
2 UMMTO - Université Mouloud Mammeri [Tizi Ouzou]

(BiFeO3)((1-x)Lambda)/(LaFeO3)(x Lambda) superlattices (SLs) with varying x have been grown by pulsed laser deposition on (111) oriented SrTiO3 substrates. In order to obtain good epitaxy and flat samples, a conducting SrRuO3 buffer has been deposited prior to the superlattices to screen the polar mismatch for such (111) SrTiO3 orientation. X-ray diffraction reciprocal space mapping on a different family of planes was collected and evidenced a room temperature structural change at x = 0.5 from a rhombohedral/monoclinic structure for rich BiFeO3 to an orthorhombic symmetry for rich LaFeO3. This symmetry change has been confirmed by Raman spectroscopy and demonstrates the different phase stability compared to similar SLs grown on (100) SrTiO3. The strongly anisotropic strain and oxygen octahedral rotation/tilt system compatibility at the interfaces probably explain the orientation dependence of the phase stability in such superlattices. Published by AIP Publishing.

Domaines: Matière Condensée [cond-mat]

J. Belhadi, S. Yousfi, H. Bouyanfif, M. El Marssi. Structural investigation of (111) oriented (BiFeO3)((1-x)Lambda)/(LaFeO3)(x Lambda) superlattices by X-ray diffraction and Raman spectroscopy. Journal of Applied Physics, 2018, 123 (15), ⟨10.1063/1.5032085⟩. ⟨hal-03627239⟩