Fluctuation-driven transitions in localized insulators: Intermittent metallicity and path chaos precede delocalization
| Autor: | Valentina Ros, Markus Müller |
|---|---|
| Přispěvatelé: | Laboratoire de Physique Théorique et Modèles Statistiques (LPTMS), Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), ANR-10-LABX-0039,PALM,Physics: Atoms, Light, Matter(2010), ANR-10-LABX-0010,ENS-ICFP,ENS- International Center for Fundamental Physics and its interfaces(2010), ANR-10-IDEX-0001,PSL,Paris Sciences et Lettres(2010), European Project: 218744,EC:FP7:TPT,FP7-SST-2007-RTD-1,EPOCH(2009) |
| Jazyk: | angličtina |
| Rok vydání: | 2021 |
| Předmět: |
Physics
[PHYS]Physics [physics] Chaos (genus) Statistical Mechanics (cond-mat.stat-mech) Condensed matter physics biology Metallicity FOS: Physical sciences Thermal fluctuations Conductance Insulator (electricity) Disordered Systems and Neural Networks (cond-mat.dis-nn) Condensed Matter - Disordered Systems and Neural Networks biology.organism_classification 01 natural sciences 010305 fluids & plasmas Delocalized electron 0103 physical sciences Path (graph theory) Condensed Matter::Strongly Correlated Electrons 010306 general physics Condensed Matter - Statistical Mechanics |
| Zdroj: | Physical Review B Physical Review B, American Physical Society, 2021, 104 (9), ⟨10.1103/PhysRevB.104.094205⟩ Physical Review B, 2021, 104 (9), ⟨10.1103/PhysRevB.104.094205⟩ |
| ISSN: | 2469-9950 2469-9969 |
| Popis: | We study how interacting localized degrees of freedom are affected by slow thermal fluctuations that change the effective local disorder. We compute the time-averaged (annealed) conductance in the insulating regime and find three distinct insulating phases, separated by two transitions. The first occurs between a non-resonating insulator and an intermittent metal. The average conductance is always dominated by rare temporal fluctuations. However, in the intermittent metal, they are so strong that the system becomes metallic for an exponentially small fraction of the time. A second transition occurs within that phase. At stronger disorder, there is a single optimal path providing the dominant contribution to the conductance at all times, but closer to delocalization, a transition to a phase with fluctuating paths occurs. This last phase displays the quantum analogon of configurational chaos in glassy systems in that thermal fluctuations induce significant changes of the dominant decay channels. While in the insulator the annealed conductance is strictly bigger than the conductance with typical, frozen disorder, we show that the threshold to delocalization is insensitive to whether or not thermal fluctuations are admitted. This rules out a potential bistability, at fixed disorder, of a localized phase with suppressed internal fluctuations and a delocalized, internally fluctuating phase. Comment: v2 with revised introduction and extended discussion, phase diagram as a function of temperature added |
| Databáze: | OpenAIRE |
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