Burgy, J.Mayr, M.Martín Mayor, VíctorMoreno, A.Dagotto, E.2023-06-202023-06-202001-12-310031-900710.1103/PhysRevLett.87.277202https://hdl.handle.net/20.500.14352/60323© 2001 The American Physical Society. This work was supported by NSF-DMR-9814350 and the Computational Science and Information Technology school at Florida State University. The authors thank Y. Ando, D. N. Argyriou, S. L. Cooper, J. C. S. Davis, R. Decca, A. Feiguin, D. Gingold, N. Nagaosa, S. Sachdev, T. Senthil, P. Schiffer, and Y. Tokura for comments.The influence of quenched disorder on the competition between ordered states separated by a firstorder transition is investigated. A phase diagram with features resembling quantum-critical behavior is observed, even using classical models. The low-temperature paramagnetic regime consists of coexisting ordered clusters, with randomly oriented order parameters. Extended to manganites, this state is argued to have a colossal magnetoresistance effect. A scale T* for cluster formation is discussed. This is the analog of the Griffiths temperature, but for the case of two competing orders, producing a strong susceptibility to external fields. Cuprates may have similar features, compatible with the large proximity effect of the very underdoped regime.engjournal articlehttp://dx.doi.org/10.1103/PhysRevLett.87.277202https://journals.aps.orgopen access531st-order phase-transitionsT-CManganitesSeparationSuperconductivityAlgorithmMagnetoresistanceLa(2-x)Sr(x)CuO(4)ResistivityPercolation.Física-Modelos matemáticos