Ground state phase diagram of the one-dimensional t–J model with pair hopping terms

Journal article

The $t$–$J$ model is a standard model of strongly correlated electrons, often studied in the context of high-$T_c$ superconductivity. However, most studies of this model neglect three-site terms, which appear at the same order as the superexchange $J$. As these terms correspond to pair-hopping, they are expected to play an important role in the physics of superconductivity when doped sufficiently far from half-filling. In this paper we present a density matrix renormalisation group study of the one-dimensional $t$–$J$ model with the pair hopping terms included. We demonstrate that these additional terms radically change the one-dimensional ground state phase diagram, extending the superconducting region at low fillings, while at larger fillings, superconductivity is completely suppressed. We explain this effect by introducing a simplified effective model of repulsive hardcore bosons.

Authors: Coulthard, J; Clark, SR; Jaksch, D

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: American Physical Society
• Journal: Physical Review B: Condensed matter and materials physics
• Publication date: 2018-07-13
• Acceptance date: 2018-06-29
• DOI: 10.1103/PhysRevB.98.035116
• EISSN: 1550-235X
• ISSN: 1098-0121
• Keywords: DMRG; Hubbard model; t-J model