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arXiv · 0903.2918

Underlying Fermi surface of Sr$_{14-x}$Ca$_x$Cu$_{24}$O$_{41}$ in two-dimensional momentum space observed by angle-resolved photoemission spectroscopy

T. Yoshida·X. J. Zhou·Z. Hussain·Z. -X. Shen·A. Fujimori·H. Eisaki·S. Uchida
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Abstract

We have performed an angle-resolved photoemission study of the two-leg ladder system Sr$_{14-x}$Ca$_x$Cu$_{24}$O$_{41}$ with $x$= 0 and 11. "Underlying Fermi surfaces" determined from low energy spectral weight mapping indicates the quasi-one dimensional nature of the electronic structure. Energy gap caused by the charge density wave has been observed for $x$=0 and the gap tends to close with Ca substitution. The absence of a quasi-particle peak even in $x$=11 is in contrast to the two-dimensional high-$T_c$ cuprates, implying strong carrier localization related to the hole crystalization.

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T. Yoshida, X. J. Zhou, Z. Hussain, Z. -X. Shen, A. Fujimori, H. Eisaki, S. Uchida. 2009-03-17. Underlying Fermi surface of Sr$_{14-x}$Ca$_x$Cu$_{24}$O$_{41}$ in two-dimensional momentum space observed by angle-resolved photoemission spectroscopy. https://doi.org/10.1103/physrevb.80.052504

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