title: Nonequilibrium fluctuations as a distinctive feature of weak localization.
abstract: Two-dimensional materials, such as graphene, topological insulators, and two-dimensional electron gases, represent a technological playground to develop coherent electronics. In these systems, quantum interference effects, and in particular weak localization, are likely to occur. These coherence effects are usually characterized by well-defined features in dc electrical transport, such as a resistivity increase and negative magnetoresistance below a crossover temperature. Recently, it has been shown that in magnetic and superconducting compounds, undergoing a weak-localization transition, a specific low-frequency 1/f noise occurs. An interpretation in terms of nonequilibrium universal conductance fluctuations has been given. The universality of this unusual electric noise mechanism has been here verified by detailed voltage-spectral density investigations on ultrathin copper films. The reported experimental results validate the proposed theoretical framework, and also provide an alternative methodology to detect weak-localization effects by using electric noise spectroscopy.
authors.affiliation: 1] Dipartimento di Fisica "E.R. Caianiello", Università di Salerno, I-84084 Fisciano, Salerno, Italy [2] CNR-SPIN, UOS di Salerno, I-84084 Fisciano, Salerno, Italy.
authors.forename: C
authors.initials: C
authors.lastname: Barone
authors.affiliation: 1] Dipartimento di Fisica "E.R. Caianiello", Università di Salerno, I-84084 Fisciano, Salerno, Italy [2] CNR-SPIN, UOS di Salerno, I-84084 Fisciano, Salerno, Italy.
authors.forename: F
authors.initials: F
authors.lastname: Romeo
authors.affiliation: 1] Dipartimento di Fisica "E.R. Caianiello", Università di Salerno, I-84084 Fisciano, Salerno, Italy [2] CNR-SPIN, UOS di Salerno, I-84084 Fisciano, Salerno, Italy.
authors.forename: S
authors.initials: S
authors.lastname: Pagano
authors.affiliation: 1] Dipartimento di Fisica "E.R. Caianiello", Università di Salerno, I-84084 Fisciano, Salerno, Italy [2] CNR-SPIN, UOS di Salerno, I-84084 Fisciano, Salerno, Italy.
authors.forename: C
authors.initials: C
authors.lastname: Attanasio
authors.affiliation: 1] Dipartimento di Fisica "E.R. Caianiello", Università di Salerno, I-84084 Fisciano, Salerno, Italy [2] CNR-SPIN, UOS di Salerno, I-84084 Fisciano, Salerno, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Carapella
authors.affiliation: 1] Dipartimento di Fisica "E.R. Caianiello", Università di Salerno, I-84084 Fisciano, Salerno, Italy [2] CNR-SPIN, UOS di Salerno, I-84084 Fisciano, Salerno, Italy.
authors.forename: C
authors.initials: C
authors.lastname: Cirillo
authors.affiliation: 1] CNR-SPIN, UOS di Salerno, I-84084 Fisciano, Salerno, Italy [2] Dipartimento di Ingegneria dell'Informazione, Ingegneria Elettrica e Matematica Applicata, Università di Salerno, I-84084 Fisciano, Salerno, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Galdi
authors.affiliation: CNR-SPIN, UOS di Salerno, I-84084 Fisciano, Salerno, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Grimaldi
authors.affiliation: 1] Dipartimento di Fisica "E.R. Caianiello", Università di Salerno, I-84084 Fisciano, Salerno, Italy [2] CNR-SPIN, UOS di Salerno, I-84084 Fisciano, Salerno, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Guarino
authors.affiliation: 1] Dipartimento di Fisica "E.R. Caianiello", Università di Salerno, I-84084 Fisciano, Salerno, Italy [2] CNR-SPIN, UOS di Salerno, I-84084 Fisciano, Salerno, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Leo
authors.affiliation: 1] Dipartimento di Fisica "E.R. Caianiello", Università di Salerno, I-84084 Fisciano, Salerno, Italy [2] CNR-SPIN, UOS di Salerno, I-84084 Fisciano, Salerno, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Nigro
authors.affiliation: 1] Dipartimento di Fisica "E.R. Caianiello", Università di Salerno, I-84084 Fisciano, Salerno, Italy [2] CNR-SPIN, UOS di Salerno, I-84084 Fisciano, Salerno, Italy.
authors.forename: P
authors.initials: P
authors.lastname: Sabatino