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arXiv · 0901.4658

Self-Doping Induced Orbital-Selective Mott Transition in Hg2Ru2O7

L. Craco·M. S. Laad·S. Leoni·H. Rosner
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Abstract

Pyrochlore oxides are fascinating systems where strong, multi-orbital correlations in concert with geometrical frustration give rise to unanticipated physical properties. The detailed mechanism of the insulator-metal transitions (IMT) underpinning these phenomena is, however, ill-understood in general. Motivated thereby, we study the IMT in the pyrochlore ${\rm Hg_{2}Ru_{2}O_{7}}$ using LDA+DMFT. In contrast to the well-known examples of Mott transitions in TMO, we show that, in the negative charge-transfer situation characteristic of \hg, self-doping plays a crucial role in the emergence of an orbital-selective IMT. We argue that this mechanism has broader relevance to other correlated pyrochlore oxides.

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L. Craco, M. S. Laad, S. Leoni, H. Rosner. 2009-01-29. Self-Doping Induced Orbital-Selective Mott Transition in Hg2Ru2O7. https://doi.org/10.1103/physrevb.79.075125

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