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arXiv · 2101.04689

From high-$T_c$ to low-$T_c$: Multi-orbital effects in transition metal oxides

Michael Klett·Tilman Schwemmer·Sebastian Wolf·Xianxin Wu·David Riegler·Andreas Dittmaier·Domenico Di Sante·Gang Li·Werner Hanke·Stephan Rachel·Ronny Thomale
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Abstract

Despite the structural resemblance of certain cuprate and nickelate parent compounds there is a striking spread of $T_c$ among such transition metal oxide superconductors. We adopt a minimal two-orbital $e_g$ model which covers cuprates and nickelate heterostructures in different parametric limits, and analyse its superconducting instabilities. The joint consideration of interactions, doping, Fermiology, and in particular the $e_g$ orbital splitting allows us to explain the strongly differing pairing propensities in cuprate and nickelate superconductors.

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Michael Klett, Tilman Schwemmer, Sebastian Wolf, Xianxin Wu, David Riegler, Andreas Dittmaier, Domenico Di Sante, Gang Li, Werner Hanke, Stephan Rachel, Ronny Thomale. 2021-01-12. From high-$T_c$ to low-$T_c$: Multi-orbital effects in transition metal oxides. https://doi.org/10.1103/physrevb.104.l100502

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