Bond excitations in the pseudogap phase of the Hubbard model

Article

关键词: QUANTUM ANTIFERROMAGNETS;    ELECTRON-SYSTEMS;    MOTT INSULATOR;    GROUND-STATES;    METALS;    SUPERCONDUCTORS;   

DOI  :  10.1103/PhysRevB.78.241101

来源: SCIE

【 摘 要 】

Using the dynamical cluster approximation, we calculate the correlation functions associated with the nearest-neighbor bond operator which measure the z component of the spin exchange in the two-dimensional Hubbard model with U equal to the bandwidth. We find that in the pseudogap region, the local bond susceptibility diverges at T=0. This shows the existence of degenerate bond spin excitation and implies quantum criticality and bond order formation when long-range correlations are considered. The strong correlation between excitations on parallel neighboring bonds suggests bond singlet dimerization. The suppression of divergence for n

【 授权许可】

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