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Angle-resolved photoemission study of insulating and metallic Cu-O chains in PrBa$_2$Cu$_3$O$_7$ and PrBa$_2$Cu$_4$O$_8$

T. Mizokawa·C. Kim·Z. -X. Shen·A. Ino·T. Yoshida·A. Fujimori·M. Goto·H. Eisaki·S. Uchida·M. Tagami·K. Yoshida·A. I. Rykov·Y. Siohara·K. Tomimoto·S. Tajima·Yuh Yamada·S. Horii·N. Yamada·Yasuji Yamada·I. Hirabayashi
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Abstract

We compare the angle-resolved photoemission spectra of the hole-doped Cu-O chains in PrBa$_2$Cu$_3$O$_7$ (Pr123) and in PrBa$_2$Cu$_4$O$_8$ (Pr124). While, in Pr123, a dispersive feature from the chain takes a band maximum at $k_b$ (momentum along the chain) $\sim$ $π/4$ and loses its spectral weight around the Fermi level, it reaches the Fermi level at $k_b$ $\sim$ $π/4$ in Pr124. Although the chains in Pr123 and Pr124 are approximately 1/4-filled, they show contrasting behaviors: While the chains in Pr123 have an instability to charge ordering, those in Pr124 avoid it and show an interesting spectral feature of a metallic coupled-chain system.

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T. Mizokawa, C. Kim, Z. -X. Shen, A. Ino, T. Yoshida, A. Fujimori, M. Goto, H. Eisaki, S. Uchida, M. Tagami, K. Yoshida, A. I. Rykov, Y. Siohara, K. Tomimoto, S. Tajima, Yuh Yamada, S. Horii, N. Yamada, Yasuji Yamada, I. Hirabayashi. 2000-11-07. Angle-resolved photoemission study of insulating and metallic Cu-O chains in PrBa$_2$Cu$_3$O$_7$ and PrBa$_2$Cu$_4$O$_8$. https://doi.org/10.1103/physrevlett.85.4779

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