Competition of spatially inhomogeneous states in antiferromagnetic Hubbard model

Abstract

In this work we study zero-temperature phases of the anisotropic Hubbard model on a three-dimensional cubic lattice in a weak coupling regime. It is known that, at half-filling, the ground state of this model is antiferromagnetic (commensurate spin-density wave). For non-zero doping, various types of spatially inhomogeneous phases, such as phase-separated states and the state with domain walls ("soliton lattice"), can emerge. Using the mean-field theory, we evaluate the free energies of these phases to determine which of them could become the true ground state in the limit of small doping. Our study demonstrates that the free energies of all discussed states are very close to each other. Smallness of these energy differences suggests that, for a real material, numerous factors, unaccounted by the model, may arbitrary shift the relative stability of the competing phases. This further implies that purely theoretical prediction of the true ground state in a particular many-fermion system is unreliable.

12 pages, 8 figures, better quality figures, some minor modifications to the text

References in corpus (11)

• Electronic phase separation in the slightly underdoped iron pnictide superconductor Ba(1-x)K(x)Fe(2)As(2)
• BEC-BCS crossover, phase transitions and phase separation in polarized resonantly-paired superfluids
• Broken translational and rotational symmetry via charge stripe order in underdoped YBCO
• Metal-insulator transition and phase separation in doped AA-stacked graphene bilayers
• Intrinsic arrested nanoscale phase separation near a topological Lifshitz transition in strongly correlated two-band metals
• AA-stacked bilayer graphene in an applied electric field: Tunable antiferromagnetism and coexisting exciton order parameter
• Phase separation of antiferromagnetic ground states in systems with imperfect nesting
• Jahn-Teller distortions and phase separation in doped manganites
• Magnetic field effects in electron systems with imperfect nesting
• Dynamical spin susceptibility of spin-valley half-metal
• Competition between different order parameters in a quasi-one-dimensional superconductor

Cited by in corpus (5)

• Complex spin-density-wave ordering in La${}_4$Ni${}_3$O${}_{10}$
• Ordering in SU(4)-symmetric model of AA bilayer graphene
• Coexistence of nematic superconductivity and spin density wave in magic-angle twisted bilayer graphene
• Mean-field analysis of a Hubbard interaction on Bernal Bilayer Graphene
• Nesting-driven ferromagnetism of itinerant electrons