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arXiv · 2006.09058

Dynamical response and competing orders in two-band Hubbard model

A. Niyazi·D. Geffroy·J. Kuneš
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Abstract

We present a dynamical mean-field study of two-particle dynamical response functions in two-band Hubbard model across several phase transitions. We observe that the transition between theexcitonic condensate and spin-state ordered state is continuous with a narrow strip of supersolidphase separating the two. Approaching transition from the excitonic condensate is announced bysoftening of the excitonic mode at theMpoint of the Brillouin zone. Inside the spin-state orderedphase there is a magnetically ordered state with 2x2 periodicity, which has no precursor in thenormal phase.

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A. Niyazi, D. Geffroy, J. Kuneš. 2020-06-16. Dynamical response and competing orders in two-band Hubbard model. https://doi.org/10.1103/physrevb.102.085159

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