Trimers in the Extended Hubbard Model

Abstract

The Lieb theorem is a cornerstone of quantum magnetism theory in condensed matter. In this work, we investigate the instability of the Lieb insulating ferrimagnetic phase in the extended Hubbard model on a trimer chain at half-filling, with one electron per site, under increasing the nearest-neighbor Coulomb coupling $V$. Our results show that despite a noticeable increase in doublon density with $V$, the ferrimagnetic insulating phase remains robust up to the phase separation (PS) line, which is observed at $V\gtrsim U/4$, where $U$ is the local Coulomb repulsion. Above the PS line, one of the coexisting phases is primarily populated by doublons on one of the two sublattices of the chain. This phase coexists with a metallic, unsaturated ferromagnetic phase for $U\gtrsim t$, and with a singlet phase for $U\lesssim t$, where $t$ is the intra-trimer hopping amplitude. We estimate the PS and the crossover lines with the help of density matrix renormalization group calculations.

10 pages, 10 figures

References in corpus (26)

• The density-matrix renormalization group
• The ITensor Software Library for Tensor Network Calculations
• Stripe order in the underdoped region of the two-dimensional Hubbard model
• The Hubbard Model
• Bond-order-wave phase and quantum phase transitions in the one-dimensional extended Hubbard model
• Edge states in trimer lattices
• Ground-state phase diagram of a half-filled one-dimensional extended Hubbard model
• Phase Diagram of One-Dimensional Extended Hubbard Model at Half Filling
• Ground state phases of the Half-Filled One-Dimensional Extended Hubbard Model
• Nature of the spin dynamics and 1/3 magnetization plateau in azurite
• Phase diagram of the one-dimensional half-filled extended Hubbard model
• Magnetic properties of the $S=1/2$ distorted diamond chain at T=0
• Dimerization in a half-filled one-dimensional extended Hubbard model
• Stripes and spin-density waves in the doped two-dimensional Hubbard model: ground state phase diagram
• Thermodynamics of Spin-1/2 AF-AF-F and F-F-AF Trimerized Quantum Heisenberg Chains
• Origin and fate of the pseudogap in the doped Hubbard model
• Spin Configuration in the 1/3 Magnetization Plateau of Azurite Determined by NMR
• Fractional and composite excitations of antiferromagnetic quantum spin trimer chains
• Doped AB_2 Hubbard Chain: Spiral, Nagaoka and RVB States, Phase Separation and Luttinger Liquid Behavior
• Bulk-boundary correspondence in extended trimer Su-Schrieffer-Heeger model
• Quasi-One-Dimensional Quantum Ferrimagnets
• Modified strong-coupling treatment of a spin-1/2 Heisenberg trimerized chain developed from the exactly solved Ising-Heisenberg diamond chain
• Low temperature pseudo-phase transition in an extended Hubbard diamond chain
• Ground-state phase diagram and thermodynamics of coupled trimer chains
• Magnetic and nonmagnetic phases in doped AB2 t-J Hubbard chains
• Unusual low-temperature behavior in the half-filled band of the one-dimensional extended Hubbard model in atomic limit