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arXiv · 1611.08399

Electronic structure of buried LaNiO3 layers in (111)-oriented LaNiO3/LaMnO3 superlattices probed by soft x-ray ARPES

F. Y. Bruno·M. Gibert·S. McKeown Walker·O. E. Peil·A. de la Torre·S. Riccò·Z. Wang·S. Catalano·A. Tamai·F. Bisti·V. N. Strocov·J-M Triscone·F. Baumberger
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Abstract

Taking advantage of the large electron escape depth of soft x-ray angle resolved photoemission spectroscopy we report electronic structure measurements of (111)-oriented [LaNiO3/LaMnO3] superlattices and LaNiO3 epitaxial films. For thin films we observe a 3D Fermi surface with an electron pocket at the Brillouin zone center and hole pockets at the zone vertices. Superlattices with thick nickelate layers present a similar electronic structure. However, as the thickness of the LaNiO3 is reduced the superlattices become insulating. These heterostructures do not show a marked redistribution of spectral weight in momentum space but exhibit a pseudogap of 50 meV.

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F. Y. Bruno, M. Gibert, S. McKeown Walker, O. E. Peil, A. de la Torre, S. Riccò, Z. Wang, S. Catalano, A. Tamai, F. Bisti, V. N. Strocov, J-M Triscone, F. Baumberger. 2016-11-25. Electronic structure of buried LaNiO3 layers in (111)-oriented LaNiO3/LaMnO3 superlattices probed by soft x-ray ARPES. https://doi.org/10.1063/1.4973558

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