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arXiv · 2306.13251

Influence of oxygen-coordination number on the electronic structure of single-layer La-based cuprates

M. Horio·X. Peiao·M. Miyamoto·T. Wada·K. Isomura·J. Osiecki·B. Thiagarajan·C. M. Polley·K. Tanaka·M. Kitamura·K. Horiba·K. Ozawa·T. Taniguchi·M. Fujita·I. Matsuda
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Abstract

We present an angle-resolved photoemission spectroscopy study of the single-layer T*-type structured cuprate SmLa$_{1-x}$Sr$_x$CuO$_4$ with unique five-fold pyramidal oxygen coordination. Upon varying oxygen content, T*-SmLa$_{1-x}$Sr$_x$CuO$_4$ evolved from a Mott-insulating to a metallic state where the Luttinger sum rule breaks down under the assumption of a large hole-like Fermi surface. This is in contrast with the known doping evolution of the structural isomer La$_{2-x}$Sr$_x$CuO$_4$ with six-fold octahedral coordination. In addition, quantitatively characterized Fermi surface suggests that the empirical $T_\mathrm{c}$ rule for octahedral oxygen-coordination systems does not apply to T*-SmLa$_{1-x}$Sr$_x$CuO$_4$. The present results highlight unique properties of the T*-type cuprates possibly rooted in its oxygen coordination, and necessitate thorough investigation with careful evaluation of disorder effects.

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M. Horio, X. Peiao, M. Miyamoto, T. Wada, K. Isomura, J. Osiecki, B. Thiagarajan, C. M. Polley, K. Tanaka, M. Kitamura, K. Horiba, K. Ozawa, T. Taniguchi, M. Fujita, I. Matsuda. 2023-06-23. Influence of oxygen-coordination number on the electronic structure of single-layer La-based cuprates. https://doi.org/10.1103/physrevb.108.035105

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