Metal-insulator transition in the one-dimensional Holstein model at half filling

Article

关键词: MOLECULAR-CRYSTAL MODEL;    QUANTUM-LATTICE FLUCTUATIONS;    SCHRIEFFER-HEEGER MODEL;    MATRIX RENORMALIZATION-GROUP;    ELECTRON-PHONON SYSTEMS;    PEIERLS DIMERIZATION;    SPINLESS FERMIONS;    PHASE-DIAGRAM;    POLARON PROBLEM;    MONTE-CARLO;   

DOI  :  10.1103/PhysRevB.60.7950

来源: SCIE

【 摘 要 】

We study the one-dimensional Holstein model with spin-1/2 electrons at half filling. Ground-state properties are calculated for long chains with great accuracy using the density-matrix renormalization-group method and extrapolated to the thermodynamic Limit. We show that for small electron-phonon coupling or large phonon frequency, the insulating Peierls ground state predicted by mean-field theory is destroyed by quantum lattice fluctuations and that the system remains in a metallic phase with a nondegenerate ground state and power-law electronic and phononic correlations. When the electron-phonon coupling becomes large or the phonon frequency small, the system undergoes a transition to an insulating Peierls phase with a twofold degenerate ground state, long-range charge-density-wave order, a dimerized lattice structure, and a gap in the electronic excitation spectrum. [S0163-1829(99)09035-9].

【 授权许可】

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