title: Two scenarios for quantum multifractality breakdown.
abstract: We expose two scenarios for the breakdown of quantum multifractality under the effect of perturbations. In the first scenario, multifractality survives below a certain scale of the quantum fluctuations. In the other one, the fluctuations of the wave functions are changed at every scale and each multifractal dimension smoothly goes to the ergodic value. We use as generic examples a one-dimensional dynamical system and the three-dimensional Anderson model at the metal-insulator transition. Based on our results, we conjecture that the sensitivity of quantum multifractality to perturbation is universal in the sense that it follows one of these two scenarios depending on the perturbation. We also discuss the experimental implications.
authors: Université de Toulouse, UPS, Laboratoire de Physique Théorique (IRSAMC), F-31062 Toulouse, France and CNRS, LPT (IRSAMC), F-31062 Toulouse, France.
authors: R
authors: R
authors: Dubertrand
authors: Instituto de Investigaciones Físicas de Mar del Plata (IFIMAR), CONICET-UNMdP, Funes 3350, B7602AYL Mar del Plata, Argentina and Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), Avenida Rivadavia 1917, Ciudad Autónoma de Buenos Aires C1033AAJ, Argentina.
authors: I
authors: I
authors: García-Mata
authors: Université de Toulouse, UPS, Laboratoire de Physique Théorique (IRSAMC), F-31062 Toulouse, France and CNRS, LPT (IRSAMC), F-31062 Toulouse, France.
authors: B
authors: B
authors: Georgeot
authors: LPTMS, CNRS and Université Paris-Sud, UMR 8626, Bât. 100, 91405 Orsay, France.
authors: O
authors: O
authors: Giraud
authors: Université de Toulouse, UPS, Laboratoire de Physique Théorique (IRSAMC), F-31062 Toulouse, France and CNRS, LPT (IRSAMC), F-31062 Toulouse, France.
authors: G
authors: G
authors: Lemarié
authors: Institut de Physique Nucléaire, Atomique et de Spectroscopie, Université de Liège, Bât. B15, B-4000 Liège, Belgium.
authors: J
authors: J
authors: Martin