Role of Hund's splitting in electronic phase competition in ${\rm Pb}_{1-x}{\rm Sn}_{x}{\rm Te}$

S. Kundu; V. Tripathi

doi:10.1103/physrevb.96.205111

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arXiv · 1704.07437

Role of Hund's splitting in electronic phase competition in ${\rm Pb}_{1-x}{\rm Sn}_{x}{\rm Te}$

S. Kundu·V. Tripathi

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Abstract

We study the effect of Hund's splitting of repulsive interactions on electronic phase transitions in the multiorbital topological crystalline insulator Pb$_{1-x}$Sn$_{x}$Te, when the chemical potential is tuned to the vicinity of low-lying Type-II Van Hove singularities. Nontrivial Berry phases associated with the Bloch states impart momentum-dependence to electron interactions in the relevant band. We use a multipatch parquet renormalization group (RG) analysis for studying the competition of different electronic phases, and find that if the dominant fixed-point interactions correspond to antiparallel spin configurations, then a chiral $p$-wave Fulde-Ferrell-Larkin-Ovchinnikov(FFLO) state is favored, otherwise, none of the commonly encountered electronic instabilities occur within the one-loop parquet RG approach.

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S. Kundu, V. Tripathi. 2017-11-08. Role of Hund's splitting in electronic phase competition in ${\rm Pb}_{1-x}{\rm Sn}_{x}{\rm Te}$. https://doi.org/10.1103/physrevb.96.205111

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