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Electron-spectroscopic investigation of metal-insulator transition in Sr2Ru1-xTixO4 (x=0.0-0.6)

Sugata Ray·D. D. Sarma·R. Vijayaraghavan
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Abstract

We investigate the nature and origin of the metal-insulator transition in Sr2Ru1-xTixO4 as a function of increasing Ti content (x). Employing detailed core, valence, and conduction band studies with x-ray and ultraviolet photoelectron spectroscopies along with Bremsstrahlung isochromat spectroscopy, it is shown that a hard gap opens up for Ti content greater than equal to 0.2, while compositions with x<0.2 exhibit finite intensity at the Fermi energy. This establishes that the metal-insulator transition in this homovalent substituted series of compounds is driven by Coulomb interaction leading to the formation of a Mott gap, in contrast to transitions driven by disorder effects or band flling.

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Sugata Ray, D. D. Sarma, R. Vijayaraghavan. 2006-04-03. Electron-spectroscopic investigation of metal-insulator transition in Sr2Ru1-xTixO4 (x=0.0-0.6). https://doi.org/10.1103/physrevb.73.165105

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