RT Journal Article T1 Absence of weak localization in two-dimensional disordered Frenkel lattices A1 Rodriguez, A. A1 Martín-Delgado Alcántara, Miguel Ángel A1 Rodriguez-Laguna, J. A1 Sierra, G. A1 Malyshev, Andrey A1 Domínguez-Adame Acosta, Francisco A1 Lemaistre, I. J. AB The standard one-parameter scaling theory predicts that all eigenstates in two-dimensional random lattices are weakly localized. We show that this claim fails in two-dimensional dipolar Frenkel exciton systems. The linear energy dispersion at the top of the exciton band, originating from the long-range inter-site coupling of dipolar nature, yields the same size-scaling law for the level spacing and the effective disorder seen by the exciton. This finally results in the delocalization of those eigenstates in the thermodynamic limit. Large scale numerical simulations allow us to perform a detailed multifractal analysis and to elucidate the nature of the excitonic eigenstates. PB Elsevier Science BV SN 0022-2313 YR 2001 FD 2001-12 LK https://hdl.handle.net/20.500.14352/59351 UL https://hdl.handle.net/20.500.14352/59351 LA eng NO © 2001 Elsevier Science B.V. All rights reserved.International Conference on Dynamical Proces Excited States of Solids (30. 2001. Villeurbanne, Francia)The authors thank E. Macía, A. Sánchez, E. Díez, R. Römer and M. Hilke for discussions. F. D-A. and A. R. were supported by DGI-MCyT (Project MAT2000-0734). V. A. M. acknowledges support from INTAS (Project No. 97-10434). NO DGI-MCyT NO INTAS DS Docta Complutense RD 13 abr 2025