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arXiv · 1005.3314

Optical probe of strong correlations in LaNiO$_{3} $ thin films

M. K. Stewart·Jian Liu·R. K. Smith·B. C. Chapler·C. - H. Yee·K. Haule·J. Chakhalian·D. N. Basov
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Abstract

The optical properties of LaNiO$_3$ thin films are investigated over a wide energy and temperature range. Thin films of varying thickness were epitaxially grown by pulsed laser deposition on LaAlO$_3$ and SrTiO$_3$ substrates. The optical conductivity data of the films reveal a number of interband transitions above 1 eV which are in good agreement with band structure calculations. No well defined Drude peak is observed however, in stark contrast with LDA theory predicting a finite density of states at the Fermi energy. This experimental finding of a vanishing Drude spectral weight, compared to a finite electron kinetic energy obtained from band structure calculations, highlights the importance of strong electronic correlations in LaNiO$_3$.

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M. K. Stewart, Jian Liu, R. K. Smith, B. C. Chapler, C. - H. Yee, K. Haule, J. Chakhalian, D. N. Basov. 2010-05-18. Optical probe of strong correlations in LaNiO$_{3} $ thin films. https://doi.org/10.1063/1.3614019

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