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arXiv · 2004.08047

Sensitivity of the electronic and magnetic structures of cuprate superconductors to density functional approximations

Kanun Pokharel·Christopher Lane·James W. Furness·Ruiqi Zhang·Jinliang Ning·Bernardo Barbiellini·Robert S. Markiewicz·Yubo Zhang·Arun Bansil·Jianwei Sun
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Abstract

We discuss the crystal, electronic, and magnetic structures of $\mathrm{La_{2-x}Sr_{x}CuO_{4}}$ (LSCO) for $x=0.0$ and $x=0.25$ employing 13 density functional approximations, representing the local, semi-local, and hybrid exchange-correlation approximations within the Perdew-Schmidt hierarchy. The meta-generalized gradient approximation (meta-GGA) class of functionals is found to perform well in capturing the key properties of LSCO, a prototypical high-temperature cuprate superconductor. In contrast, the local-spin-density approximation, GGA, and the hybrid density functional fail to capture the metal-insulator transition under doping.

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Kanun Pokharel, Christopher Lane, James W. Furness, Ruiqi Zhang, Jinliang Ning, Bernardo Barbiellini, Robert S. Markiewicz, Yubo Zhang, Arun Bansil, Jianwei Sun. 2020-04-17. Sensitivity of the electronic and magnetic structures of cuprate superconductors to density functional approximations. https://arxiv.org/abs/2004.08047

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