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arXiv · 1511.01371

A first principles investigation of cubic BaRuO$_3$: A Hund's metal

Nagamalleswararao Dasari·S. R. K. C. Sharma Yamijala·Manish Jain·T. Saha Dasgupta·Juana Moreno·Mark Jarrell·N. S. Vidhyadhiraja
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Abstract

A first-principles investigation of cubic-BaRuO$_3$, by combining density functional theory with dynamical mean-field theory and a hybridization expansion continuous time quantum Monte-Carlo solver, has been carried out. Non-magnetic calculations with appropriately chosen on-site Coulomb repulsion, $U$ and Hund's exchange, $J$, for single-particle dynamics and static susceptibility show that cubic-BaRuO$_3$ is in a spin-frozen state at temperatures above the ferromagnetic transition point. A strong red shift with increasing $J$ of the peak in the real frequency dynamical susceptibility indicates a dramatic suppression of the Fermi liquid coherence scale as compared to the bare parameters in cubic-BaRuO$_3$. The self-energy also shows clear deviation from Fermi liquid behaviour that manifests in the single-particle spectrum. Such a clean separation of energy scales in this system provides scope for an incoherent spin-frozen (SF) phase, that extends over a wide temperature range, to manifest in non-Fermi liquid behaviour and to be the precursor for the magnetically ordered ground state.

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Nagamalleswararao Dasari, S. R. K. C. Sharma Yamijala, Manish Jain, T. Saha Dasgupta, Juana Moreno, Mark Jarrell, N. S. Vidhyadhiraja. 2015-12-13. A first principles investigation of cubic BaRuO$_3$: A Hund's metal. https://doi.org/10.1103/physrevb.94.085143

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