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Photoemission Spectral Weight Transfer and Mass Renormalization in the Fermi-Liquid System La$_{1-x}$Sr$_x$TiO$_{3+y/2}$

T. Yoshida·A. Ino·T. Mizokawa·A. Fujimori·Y. Taguchi·T. Katsufuji·Y. Tokura
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Abstract

We have performed a photoemission study of La$_{1-x}$Sr$_x$TiO$_{3+y/2}$ near the filling-control metal-insulator transition (MIT) as a function of hole doping. Mass renormalization deduced from the spectral weight and the width of the quasi-particle band around the chemical potential $μ$ is compared with that deduced from the electronic specific heat. The result implies that, near the MIT, band narrowing occurs strongly in the vicinity of $μ$. Spectral weight transfer occurs from the coherent to the incoherent parts upon antiferromagnetic ordering, which we associate with the partial gap opening at $μ$.

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T. Yoshida, A. Ino, T. Mizokawa, A. Fujimori, Y. Taguchi, T. Katsufuji, Y. Tokura. 1999-11-27. Photoemission Spectral Weight Transfer and Mass Renormalization in the Fermi-Liquid System La$_{1-x}$Sr$_x$TiO$_{3+y/2}$. https://doi.org/10.1209/epl%2Fi2002-00235-7

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