Phase separation and competition of superconductivity and magnetism in the two-dimensional Hubbard model: From strong to weak coupling

Abstract

Cooperation and competition between the antiferromagnetic, d-wave superconducting and Mott-insulating states are explored for the two-dimensional Hubbard model including nearest and next-nearest-neighbor hoppings at zero temperature. Using the variational cluster approach with clusters of different shapes and sizes up to 10 sites, it is found that the doping-driven transition from a phase with microscopic coexistence of antiferromagnetism and superconductivity to a purely superconducting phase is discontinuous for strong interaction and accompanied by phase separation. At half-filling the system is in an antiferromagnetic Mott-insulating state with vanishing charge compressibility. Upon decreasing the interaction strength U below a certain critical value of roughly U=4 (in units of the nearest-neighbor hopping), however, the filling-dependent magnetic transition changes its character and becomes continuous. Phase separation or, more carefully, the tendency towards the formation of inhomogeneous states disappears. This critical value is in contrast to previous studies, where a much larger value was obtained. Moreover, we find that the system at half-filling undergoes the Mott transition from an insulator to a state with a finite charge compressibility at essentially the same value. The weakly correlated state at half-filling exhibits superconductivity microscopically admixed to the antiferromagnetic order. This scenario suggests a close relation between phase separation and the Mott-insulator physics.

7 pages, 8 figures, revised version to be published in Phys. Rev. B

References in corpus (10)

• A `checkerboard' electronic crystal state in lightly hole-doped Ca_{2-x}Na_{x}CuO_{2}Cl_{2}
• Variational cluster approach to correlated electron systems in low dimensions
• Competition between d-wave superconductivity and antiferromagnetism in the 2D Hubbard model
• Gapless quantum spin liquid, stripe and antiferromagnetic phases in frustrated Hubbard models in two dimensions
• Renormalized mean-field analysis of antiferromagnetism and d-wave superconductivity in the two-dimensional Hubbard model
• Variational cluster approach to the Hubbard model: Phase-separation tendency and finite-size effects
• Universality Classes of Metal-Insulator Transitions in Strongly Correlated Electron Systems and Mechanism of High-Temperature Superconductivity
• Phase separation in the Hubbard model
• Coexistence of Antiferromagnetism and Superconductivity in Electron-doped High-Tc Superconductors
• Phase separation in the particle-hole asymmetric Hubbard model

Cited by in corpus (28)

• Strength of the Spin-Fluctuation-Mediated Pairing Interaction in a High-Temperature Superconductor
• Superconductivity, antiferromagnetism and phase separation in the two-dimensional Hubbard model: A dual-fermion approach
• Spatially inhomogeneous phase in the two-dimensional repulsive Hubbard model
• Competition among various charge-inhomogeneous states and d-wave superconducting state in Hubbard models on square lattices
• Magnetism and d-wave superconductivity on the half-filled square lattice with frustration
• Superconductivity, charge-density waves, antiferromagnetism, and phase separation in the Hubbard-Holstein model
• Hidden Mott transition and large-$U$ superconductivity in the two-dimensional Hubbard model
• Phase diagram and single-particle spectrum of CuO${}_2$ layers within a variational cluster approach to the 3-band Hubbard model
• The Bethe-Salpeter equation at the critical end-point of the Mott transition
• Correlation-induced superconductivity dynamically stabilized and enhanced by laser irradiation
• Effects of interaction strength, doping, and frustration on the antiferromagnetic phase of the two-dimensional Hubbard model
• Variational Monte Carlo Study of Electron Differentiation around Mott Transition
• Entropy in the non-Fermi-liquid regime of the doped $2d$ Hubbard model
• Self-Optimized Superconductivity Attainable by Interlayer Phase Separation at Cuprate Interfaces
• Interplay Between $d$-wave Superconductivity and a Bond Density Wave in the one-band Hubbard model
• Variational cluster approach to s-wave pairing in heavy-fermion superconductors
• Charge Order and Superconductivity as Competing Brothers in Cuprate High-$T_{\mathrm{c}}$ Superconductors
• Superconductivity in bilayer $t$-$t^{\prime }$ Hubbard models
• Frustration-Induced Superconductivity in the $t$-$t^{\prime }$ Hubbard Model
• Magnetic phase diagram and Mott transition of the half-filled 1/5-depleted Hubbard model with frustration
• Charge density wave solutions of the Hubbard model in the composite operator formalism
• The Weak, the Strong and the Long Correlation Regimes of the Two-Dimensional Hubbard Model at Finite Temperature
• Absence of superconductivity in the two-dimensional Hubbard model
• Electronic spectrum and superconductivity in the extended t-J-V model
• Disorder Effects on Competition between Antiferromagnetism and Superconductivity in Cuprate Superconductors through the Enhancement in Charge Susceptibility
• Magnetic properties and superconductivity in the two-dimensional repulsive Hubbard model
• Ferrimagnetism Induced by Off-Site Coulomb Interaction in an Itinerant Electron System
• Evaluating second-order phase transitions with Diagrammatic Monte Carlo: Néel Transition in the doped three-dimensional Hubbard model