Rodriguez, A.Martin-Delgado Alcántara, Miguel ÁngelRodriguez-Laguna, J.Sierra, G.Malyshev, AndreyDomínguez-Adame Acosta, FranciscoLemaistre, I. J.2023-06-202023-06-202001-12[1] E. Abrahams, P. W. Anderson, D. C. Licciardello, and V. Ramakrishnan, Phys. Rev. Lett. 42, 673 (1979). [2] M. Inui, S. A. Trugman, and E. Abrahams, Phys. Rev. B 49, 3190 (1994). [3] A. Eilmes, R. A. Römer, and M. Schreiber, Eur. Phys. J. B 1, 29 (1998); phys. stat. sol. (b) 205, 229 (1998). [4] J. C. Flores, J. Phys.: Condens. Matter 1, 8471 (1989). [5] D. H. Dunlap, H.-L. Wu, and P. Phillips, Phys. Rev. Lett. 65, 88 (1990). [6] V. Bellani, E. Diez, R. Hey, L. Toni, L. Tarricone, G. B. Parravicini, F. DomínguezAdame, and R. Gómez-Alcalá, Phys. Rev. Lett. 82, 2159 (1999). [7] D. E. Logan and P. G. Wolynes, Phys. Rev. B 29, 6560 (1984); ibid. 31, 2437 (1985); ibid. 36, 4135 (1987); J. Chem. Phys. 87, 7199 (1987). [8] L. S. Levitov, Ann. Phys. (Leipzig) 8, 507 (1999). [9] A. Rodríguez, V. A. Malyshev, and F. Domínguez-Adame, J. Phys. A: Math. Gen. 33 L161 (2000). [10] P. L. Christiansen, Yu. B. Gaididei, M. Johansson, K. Ø. Rasmussen, V. K. Mezentsev, and J. Juul Rasmussen, Phys. Rev. B 57, 11 303 (1998). [11] G. H. Golub and C. F. Van Loan, Matrix Computations (The Johns Hopkins University Press, Maryland, 1996). [12] K. H. Hoffmann and M. Schreiber (Eds.), Computational Physics (Springer, Berlin, (1996).0022-231310.1016/S0022-2313(01)00302-7https://hdl.handle.net/20.500.14352/59351© 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).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.engAbsence of weak localization in two-dimensional disordered Frenkel latticesjournal articlehttp://dx.doi.org/10.1016/S0022-2313(01)00302-7http://www.sciencedirect.com/http://arxiv.org/abs/cond-mat/0201535open access538.92-Dimensional Anderson ModelOff-Diagonal DisorderQuantum DiffusionSystemsStatesFísica de materiales