Pb$_{10-x}$Cu$_x$(PO$_4$)$_6$O: a Mott or charge transfer insulator in need of further doping for (super)conductivity

Liang Si; Markus Wallerberger; Andriy Smolyanyuk; Simone di Cataldo; Jan M. Tomczak; Karsten Held

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arXiv · 2308.04427

Pb$_{10-x}$Cu$_x$(PO$_4$)$_6$O: a Mott or charge transfer insulator in need of further doping for (super)conductivity

Liang Si·Markus Wallerberger·Andriy Smolyanyuk·Simone di Cataldo·Jan M. Tomczak·Karsten Held

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Abstract

We briefly review the status quo of research on the putative superconductor Pb$_9$Cu(PO$_4$)$_6$O also known as LK-99. Further, we provide {\em ab initio} derived tight-binding parameters for a two- and five-band model, and solve these in dynamical-mean-field theory. The ratio interaction-to-bandwidth makes LK-99 a Mott or charge transfer insulator. Electron or hole doping (which is different from substituting Pb by Cu and thus differs from LK-99) is required to make it metallic and potentially superconducting.

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Liang Si, Markus Wallerberger, Andriy Smolyanyuk, Simone di Cataldo, Jan M. Tomczak, Karsten Held. 2023-08-08. Pb$_{10-x}$Cu$_x$(PO$_4$)$_6$O: a Mott or charge transfer insulator in need of further doping for (super)conductivity. https://arxiv.org/abs/2308.04427

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