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arXiv · 1305.1161

Two-orbital view on the origin of the material dependence of Tc in the single-layer cuprates

Hirofumi Sakakibara·Hidetomo Usui·Kazuhiko Kuroki·Ryotaro Arita·Hideo Aoki
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Abstract

Using the dx2-y2+dz2 two orbital model of the high Tc cuprates obtained from the first-principle calculation, we show that the material dependence of the Fermi surface shape can be understood by the degree of the mixture between the dx2-y2$ and the dz2 orbitals. We explain, through investigating the tightbinding hopping integrals, why some cuprates have square shaped Fermi surface, while others have more rounded ones. From this viewpoint, we explain the experimentally observed correlation between the curvature of the Fermi surface and Tc.

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Hirofumi Sakakibara, Hidetomo Usui, Kazuhiko Kuroki, Ryotaro Arita, Hideo Aoki. 2013-05-06. Two-orbital view on the origin of the material dependence of Tc in the single-layer cuprates. https://doi.org/10.1088/1742-6596%2F400%2F2%2F022100

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