title: Multifractality of quantum wave functions in the presence of perturbations.
abstract: We present a comprehensive study of the destruction of quantum multifractality in the presence of perturbations. We study diverse representative models displaying multifractality, including a pseudointegrable system, the Anderson model, and a random matrix model. We apply several types of natural perturbations which can be relevant for experimental implementations. We construct an analytical theory for certain cases and perform extensive large-scale numerical simulations in other cases. The data are analyzed through refined methods including double scaling analysis. Our results confirm the recent conjecture that multifractality breaks down following two scenarios. In the first one, multifractality is preserved unchanged below a certain characteristic length which decreases with perturbation strength. In the second one, multifractality is affected at all scales and disappears uniformly for a strong-enough perturbation. Our refined analysis shows that subtle variants of these scenarios can be present in certain cases. This study could guide experimental implementations in order to observe quantum multifractality in real systems.
authors.affiliation: Université de Toulouse, UPS, Laboratoire de Physique Théorique (IRSAMC), F-31062 Toulouse, France.|CNRS; LPT (IRSAMC), UMR 5152, F-31062 Toulouse, France.|Institut de Physique Nucléaire, Atomique et de Spectroscopie, Université de Liège, Bât. B15, B-4000 Liège, Belgium.
authors.forename: R
authors.initials: R
authors.lastname: Dubertrand
authors.affiliation: Instituto de Investigaciones Físicas de Mar del Plata (IFIMAR), CONICET-UNMdP, Funes 3350, B7602AYL Mar del Plata, Argentina.|Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), Argentina.
authors.forename: I
authors.initials: I
authors.lastname: García-Mata
authors.affiliation: Université de Toulouse, UPS, Laboratoire de Physique Théorique (IRSAMC), F-31062 Toulouse, France.|CNRS; LPT (IRSAMC), UMR 5152, F-31062 Toulouse, France.
authors.forename: B
authors.initials: B
authors.lastname: Georgeot
authors.affiliation: LPTMS, CNRS, Univ. Paris-Sud, Université Paris-Saclay, 91405 Orsay, France.
authors.forename: O
authors.initials: O
authors.lastname: Giraud
authors.affiliation: Université de Toulouse, UPS, Laboratoire de Physique Théorique (IRSAMC), F-31062 Toulouse, France.|CNRS; LPT (IRSAMC), UMR 5152, F-31062 Toulouse, France.
authors.forename: G
authors.initials: G
authors.lastname: Lemarié
authors.affiliation: Institut de Physique Nucléaire, Atomique et de Spectroscopie, Université de Liège, Bât. B15, B-4000 Liège, Belgium.
authors.forename: J
authors.initials: J
authors.lastname: Martin