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arXiv · 0706.4276

Fermi pockets and correlation effects in underdoped YBa2Cu3O6.5

I. S. Elfimov·G. A. Sawatzky·A. Damascelli
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Abstract

The detection of quantum oscillations in the electrical resistivity of YBa2Cu3O6.5 provides direct evidence for the existence of Fermi surface pockets in an underdoped cuprate. We present a theoretical study of the electronic structure of YBa2Cu3O7-d (YBCO) aiming at establishing the nature of these Fermi pockets, i.e. CuO2 plane versus CuO chain or BaO. We argue that electron correlation effects, such as orbital-dependent band distortions and highly anisotropic self-energy corrections, must be taken into account in order to properly interpret the quantum oscillation experiments.

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I. S. Elfimov, G. A. Sawatzky, A. Damascelli. 2008-01-18. Fermi pockets and correlation effects in underdoped YBa2Cu3O6.5. https://doi.org/10.1103/physrevb.77.060504

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