Drude weight of the spin-1/2 XXZ chain: Density matrix renormalization group versus exact diagonalization

Article

关键词: TRANSPORT;    INTEGRABILITY;    CONDUCTIVITY;    STIFFNESS;    DYNAMICS;   

DOI  :  10.1103/PhysRevB.87.245128

来源: SCIE

【 摘 要 】

We revisit the problem of the spin Drude weight D of the integrable spin-1/2 XXZ chain using two complementary approaches, exact diagonalization (ED) and the time-dependent density-matrix renormalization group (tDMRG). We pursue two main goals. First, we present extensive results for the temperature dependence of D. By exploiting time translation invariance within tDMRG, one can extract D for significantly lower temperatures than in previous tDMRG studies. Second, we discuss the numerical quality of the tDMRG data and elaborate on details of the finite-size scaling of the ED results, comparing calculations carried out in the canonical and grand-canonical ensembles. Furthermore, we analyze the behavior of the Drude weight as the point with SU(2)-symmetric exchange is approached and discuss the relative contribution of the Drude weight to the sum rule as a function of temperature.

【 授权许可】

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