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arXiv · 2002.02276

A laser-ARPES study of LaNiO3 thin films grown by sputter deposition

Edoardo Cappelli·Willem Tromp·Siobhan McKeown Walker·Anna Tamai·Marta Gibert·Felix Baumberger·Flavio Y. Bruno
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Abstract

Thin films of the correlated transition-metal oxide LaNiO$_3$ undergo a metal-insulator transition when their thickness is reduced to a few unit cells. Here, we use angle-resolved photoemission spectroscopy to study the evolution of the electronic structure across this transition in a series of epitaxial LaNiO$_3$ films of thicknesses ranging from 19 to 2 u.c. grown in situ by RF magnetron sputtering. Our data show a strong reduction of the electronic mean free path as the thickness is reduced below 5 u.c. This prevents the system from becoming electronically two-dimensional, as confirmed by the largely unchanged Fermi surface seen in our experiments. In the insulating state we observe a strong suppression of the coherent quasiparticle peak but no clear gap. These features resemble previous observations of the insulating state of NdNiO$_3$.

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Edoardo Cappelli, Willem Tromp, Siobhan McKeown Walker, Anna Tamai, Marta Gibert, Felix Baumberger, Flavio Y. Bruno. 2020-02-06. A laser-ARPES study of LaNiO3 thin films grown by sputter deposition. https://doi.org/10.1063/1.5143316

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