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تسجيل مستخدم جديدCritical wave-packet dynamics in the power-law bond disordered Anderson Model
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نشر من قبل
Francisco Anacleto Barros Fidelis de Moura
تاريخ النشر
2005
مجال البحث
فيزياء
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English
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We investigate the wave-packet dynamics of the power-law bond disordered one-dimensional Anderson model with hopping amplitudes decreasing as $H_{nm}propto |n-m|^{-alpha}$. We consider the critical case ($alpha=1$). Using an exact diagonalization scheme on finite chains, we compute the participation moments of all stationary energy eigenstates as well as the spreading of an initially localized wave-packet. The eigenstates multifractality is characterized by the set of fractal dimensions of the participation moments. The wave-packet shows a diffusive-like spread developing a power-law tail and achieves a stationary non-uniform profile after reflecting at the chain boundaries. As a consequence, the time-dependent participation moments exhibit two distinct scaling regimes. We formulate a finite-size scaling hypothesis for the participation moments relating their scaling exponents to the ones governing the return probability and wave-function power-law decays.
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