Nanoscale dynamics and the fluctuation-dissipation-relation in an aging polymer glass

Abstract

Response functions and fluctuations measured locally in complex materials should equally well characterize mesoscopic-scale dynamics. The fluctuation-dissipation-relation (FDR), relates the two in equilibrium, a fact used regularly, for example, to infer mechanical properties of soft matter from the fluctuations in light scattering. In slowly-evolving non-equilibrium systems, such as aging spin and structural glasses, sheared soft matter, and active matter, a form of FDR has been proposed in which an effective temperature, Teff, replaces the usual temperature, and universal behavior is found in mean-field models and simulations. Thus far, only experiments on spin-glasses and liquid crystals have succeeded in accessing the strong aging regime, where Teff >T and possible scaling behavior are expected. Here we test these ideas through measurements of local dielectric response and polarization noise in an aging structural glass, poly-vinyl-acetate . The relaxation-time spectrum, as measured by noise, is compressed, and by response, is stretched, relative to equilibrium, requiring an effective temperature with a scaling behavior similar to that of certain mean-field spin-glass models.

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Cited by in corpus (19)

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• Static versus dynamic heterogeneities in the D = 3 Edwards-Anderson-Ising spin glass
• Predicting the self-assembly of a model colloidal crystal
• The modified Sutherland--Einstein relation for diffusive nonequilibria
• Controlling crystal self-assembly using a real-time feedback scheme
• A statics-dynamics equivalence through the fluctuation-dissipation ratio provides a window into the spin-glass phase from nonequilibrium measurements
• Testing statics-dynamics equivalence at the spin-glass transition in three dimensions
• Experimental Evidence of Fluctuation-Dissipation Theorem Violation in a Superspin Glass
• The cumulative overlap distribution function in realistic spin glasses
• Perspective: Time irreversibility in systems observed at coarse resolution
• Quantifying reversibility in a phase-separating lattice gas: an analogy with self-assembly
• Ubiquitous Dynamical Time Asymmetry in Measurements on Materials and Biological Systems
• Decoherence in a nonequilibrium environment
• Financial Brownian particle in the layered order book fluid and Fluctuation-Dissipation relations
• Universal Scaling in the Aging of the Strong Glass Former SiO${}_2$