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arXiv · 0712.3083

Coherent and Incoherent States of Electron-doped SrTiO3

Y. Ishida·R. Eguchi·M. Matsunami·K. Horiba·M. Taguchi·A. Chainani·Y. Senba·H. Ohashi·H. Ohta·S. Shin
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Abstract

Resonant photoemission at the Ti 2p and O 1s edges on a Nb-doped SrTiO3 thin film revealed that the coherent state (CS) at the Fermi level (EF) had mainly Ti 3d character whereas the incoherent in-gap state (IGS) positioned ~1.5 eV below EF had mixed character of Ti 3d and O 2p states. This indicates that the IGS is formed by a spectral-weight transfer from the CS and subsequent spectral-weight redistribution through d-p hybridization. We discuss the evolution of the excitation spectrum with 3d band filling and rationalize the IGS through a mechanism similar to that proposed by Haldane and Anderson.

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Y. Ishida, R. Eguchi, M. Matsunami, K. Horiba, M. Taguchi, A. Chainani, Y. Senba, H. Ohashi, H. Ohta, S. Shin. 2007-12-19. Coherent and Incoherent States of Electron-doped SrTiO3. https://doi.org/10.1103/physrevlett.100.056401

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