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Anomalous optical absorption in a random system with scale-free disorder

E. Diaz·A. Rodriguez·F. Dominguez-Adame·V. A. Malyshev
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Abstract

We report on an anomalous behavior of the absorption spectrum in a one-dimensional lattice with long-range-correlated diagonal disorder with a power-like spectrum in the form S(k) ~ 1/k^A. These type of correlations give rise to a phase of extended states at the band center, provided A is larger than a critical value A_c. We show that for A < A_c the absorption spectrum is single-peaked, while an additional peak arises when A > A_c, signalling the occurrence of the Anderson transition. The peak is located slightly below the low-energy mobility edge, providing a unique spectroscopic tool to monitor the latter. We present qualitative arguments explaining this anomaly.

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E. Diaz, A. Rodriguez, F. Dominguez-Adame, V. A. Malyshev. 2005-01-13. Anomalous optical absorption in a random system with scale-free disorder. https://doi.org/10.1209/epl%2Fi2005-10321-x

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