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Scattering at the Anderson transition: Power--law banded random matrix model

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 Publication date 2006
  fields Physics
and research's language is English




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We analyze the scattering properties of a periodic one-dimensional system at criticality represented by the so-called power-law banded random matrix model at the metal insulator transition. We focus on the scaling of Wigner delay times $tau$ and resonance widths $Gamma$. We found that the typical values of $tau$ and $Gamma$ (calculated as the geometric mean) scale with the system size $L$ as $tau^{tiny typ}propto L^{D_1}$ and $Gamma^{tiny typ} propto L^{-(2-D_2)}$, where $D_1$ is the information dimension and $D_2$ is the correlation dimension of eigenfunctions of the corresponding closed system.



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