Díaz García, ElenaRodriguez, A.Domínguez-Adame Acosta, FranciscoMalyshev, Andrey2023-06-202023-06-202005-120295-507510.1209/epl/i2005-10321-xhttps://hdl.handle.net/20.500.14352/51251© EDP Sciences The authors thank A. V. Malyshev, M. L. Lyra and F. A. B. F. de Moura for helpful comments. This work was supported by DGI-MCyT (Project MAT2003-01533) and CAM (Project GR/MAT/0039/2004). V. A. M. acknowledges support from ISTC (grant #2679).Optical spectroscopy usually fails in detecting localization-delocalization (Anderson) transitions. We report on an anomalous behavior of the absorption spectrum in a one-dimensional lattice with long-range correlated diagonal disorder, having a power-like spectrum S(k)similar to 1/k(alpha). This type of correlations gives rise to a phase of extended states at the band center, provided alpha is larger than a critical value alpha(c). We show that for alpha<alpha(c), the absorption spectrum is single-peaked, while an additional peak arises when alpha>alpha(c), signaling 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.engjournal articlehttp://dx.doi.org/10.1209/epl/i2005-10321-xhttp://iopscience.iop.orghttp://arxiv.org/abs/cond-mat/0501311restricted access538.9Metal-Insulator-TransitionCorrelated disorderMobility edgeLocalizationAbsenceDiffusionTransportChainsModelsStatesFísica de materiales