Excitonic Phase Diagram of the Three-Chain Hubbard Model for Semiconducting and Semimetallic Ta${}_2$NiSe${}_5$

Kaoru Domon, Takemi Yamada, Yoshiaki Ōno

Transition metal chalcogenide Ta${}_2$NiSe${}_5$, a promising material for the excitonic insulator, is investigated on the basis of the quasi-one-dimensional three-chain Hubbard model…