arXiv subjects

Adauto J. F. de Souza

Publications and source records attributed to Adauto J. F. de Souza.

3 recordsLinked to original sources

arXiv2026

Parametric Glassiness in Graphene-based Electronic Lévy Glass

Complex disordered conductors can display highly structured and parameter-sensitive transport even in the absence of a thermodynamically stable glass phase. Overlap distributions originally developed for replica symmetry breaking (RSB) provide a useful diagnostic of this organization, provided that their interpretation is distinguished from the equilibrium Parisi construction. In this study, we report RSB-like overlap phenomenology and parametric mesoscopic glassiness in a graphene-based electronic Lévy glass, a device that mimics optical phenomena via electronic processes. By tuning the Fermi energy, we can control the number of propagating wave modes and observe reentrant changes from narrowly centered to broad or bimodal overlap distributions. The phenomenology is observed in both graphene-based and conventional two-dimensional electron-gas electronic Lévy glasses, indicating its generality. Sample-resolved overlap distributions show that the effect is intrinsic to each disorder landscape, whereas the normalized conductance variance shows that the growth of the absolute variance is mainly caused by the increasing mean conductance. We therefore interpret the overlap as a measure of correlation among hierarchically organized transport pathways and the reentrant behavior as evidence of pinning, parameter-induced reorganizations, and mesoscopic chaos in coherent transport.

cond-mat.mes-hall↗

arXiv2026

Opinion dynamics on social proximity disordered networks

Understanding how local social pressure shapes collective opinion formation is essential in modern society, with implications in sociology, politics, finance, and technology. Complex networks are a powerful framework for investigating these processes and for representing social interactions in emergent phenomena, and canonical models such as random, scale-free, and small-world networks remain most relevant when Euclidean geometric proximity and contiguous interactions are not the dominant organizing factors. Our investigation explores the effects of Gabriel graphs, a spatially embedded network that utilizes proximity-based interactions, on social opinion dynamics. Using a geometric disorder parameter that randomly displaces agent coordinates, we transition from square lattices of social interactions to spatial random networks that preserve local constraints while introducing strong topological heterogeneity. Opinion dynamics operate through social pressure, with a level of nonconformity that affects dissent among opinions. We analyze magnetization, susceptibility, and Binder's fourth-order cumulant to characterize the emergence and breakdown of global social consensus. The model exhibits second-order phase transitions whose behavior depends on both geometric disorder and nonconformity levels. We use volumetric scaling and provide a reference frame appropriate for characterizing criticality in regular and heterogeneous interaction topologies. We find that the standard critical exponents remain compatible with the two-dimensional Ising universality class. Furthermore, the results suggest that spatially constrained, planar, and globally connected interaction topologies preserve the dimensionality of space in critical dynamics analysis.

cond-mat.stat-mech↗

arXiv2026

Multifractal and Ergodic Properties of Conductance Fluctuations under Strong Disorder

Understanding the stochastic properties of conductance fluctuations in disordered mesoscopic systems is fundamental to quantum transport. In this work, we investigate the multifractal and ergodic properties of the fictitious time series of conductance in two-dimensional tight-binding models under varying Anderson disorder. Using standard multifractal analysis, we show that conductance fluctuations exhibit a transition from non-ergodic to ergodic behavior as the disorder strength increases, as evidenced by the decay of the conductance correlation function. Remarkably, multifractality persists in both regimes; however, it becomes insensitive to shuffling in the strong-disorder (ergodic) regime, suggesting that distributional effects dominate temporal organization. On the contrary, in the weakly disordered (non-ergodic) regime, long-range correlations play a significant role. These findings are robust against changes in lead geometry (asymmetric vs. symmetric). Our results provide new insights into the interplay between ergodicity, multifractality, and rare events in disordered quantum transport.

cond-mat.mes-hall↗