Disturbance spreading in incommensurate and quasiperiodic systems

Article

关键词: FRENKEL-KONTOROVA MODEL;    QUANTUM TRANSPORT;    DEVILS STAIRCASE;    HEAT-CONDUCTION;    GOLD ATOMS;    LOCALIZATION;    DIFFUSION;    DIMENSION;    EQUATION;    SPECTRA;   

DOI  :  10.1103/PhysRevB.61.9414

来源: SCIE

【 摘 要 】

The propagation of an initially localized excitation in one-dimensional incommensurate, quasiperiodic and random systems is investigated numerically. It is discovered that the time evolution of variances sigma(2)(t) of atom displacements depends on the initial condition. For the initial condition with nonzero momentum, sigma(2()(t) goes as t(alpha) with alpha = 1 and 0 for incommensurate Frenkel-Kontorova model at V below and above V-c respectively, and alpha = I for uniform, quasiperiodic and random chains. It is also found that alpha = 1 - beta with beta the exponent of distribution function of frequency at zero frequency, i.e., rho(omega) similar to omega(beta) (as omega-->0). For the initial condition with zero momentum, alpha=0 for all systems studied. The underlying physical meaning of this diffusive behavior is discussed.

【 授权许可】

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