Thermodynamics and crossover phenomena in the correlation lengths of the one-dimensional t-J model

Article

关键词: MATRIX-RENORMALIZATION-GROUP;    LUTTINGER LIQUID PROPERTIES;    SPIN-GAP PHASE;    CRITICAL EXPONENTS;    QUANTUM-SYSTEMS;    HUBBARD-MODEL;    TEMPERATURE;    CHAIN;    DIAGRAM;   

DOI  :  10.1103/PhysRevB.66.245102

来源: SCIE

【 摘 要 】

We investigate the thermodynamics of the one-dimensional t-J model using transfer matrix renormalization group algorithms and present results for quantities like particle number, specific heat, spin susceptibility, and compressibility. Based on these results we confirm a phase diagram consisting of a Tomonaga-Luttinger liquid (TLL) phase for small J/t and a phase-separated state for J/t large. Close to phase separation we find a spin-gap (Luther-Emery) phase at low densities consistent with predictions by other studies. At the supersymmetric point we compare our results with exact results from the Bethe ansatz and find excellent agreement. In particular we focus on the calculation of correlation lengths and static correlation functions and study the crossover from the nonuniversal high-T lattice into the quantum critical regime. At the supersymmetric point we compare in detail with predictions by conformal field theory and TLL theory and show the importance of logarithmic corrections.

【 授权许可】

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