%0 Book Section %1 statphys23_0379 %A Leonard, S. %A Mayer, P. %A Sollich, P. %A Berthier, L. %A Garrahan, J.P. %B Abstract Book of the XXIII IUPAP International Conference on Statistical Physics %C Genova, Italy %D 2007 %E Pietronero, Luciano %E Loreto, Vittorio %E Zapperi, Stefano %K activated constrained dynamics effective fluctuation-dissipation glasses kinetically models ratio statphys23 temperature topic-3 %T Negative fluctuation-dissipation ratios and activated aging dynamics in kinetically constrained glass models %U http://st23.statphys23.org/webservices/abstract/preview_pop.php?ID_PAPER=379 %X We consider the dynamics of kinetically constrained models of glasses in the non-equilibrium aging regime following a sudden quench from high to low temperatures, focussing on the one-spin facilitated Fredrickson-Andersen and East models in various spatial dimensions. The detailed properties of two-time correlation and response functions are studied using a combination of theoretical approaches, including exact mappings of master operators and reductions to integrable quantum spin chains, field theory and renormalization group, and independent interval and timescale separation methods. The resulting analytical predictions are confirmed by means of detailed numerical simulations. Even though the models we consider have trivial equilibrium properties they display a surprising range of dynamic behaviour during aging, which can be directly related to the existence and growth in time of dynamic lengthscales. Well-behaved fluctuation-dissipation ratios can be defined; we confirm in particular the existence of negative fluctuation-dissipation ratios for a large number of observables. Our results suggest that well-defined violations of fluctuation-dissipation relations, of a purely dynamic origin and unrelated to the thermodynamic concept of an effective temperature, may in general be present in non-equilibrium glassy materials.

@incollection{statphys23_0379, abstract = {We consider the dynamics of kinetically constrained models of glasses in the non-equilibrium aging regime following a sudden quench from high to low temperatures, focussing on the one-spin facilitated Fredrickson-Andersen and East models in various spatial dimensions. The detailed properties of two-time correlation and response functions are studied using a combination of theoretical approaches, including exact mappings of master operators and reductions to integrable quantum spin chains, field theory and renormalization group, and independent interval and timescale separation methods. The resulting analytical predictions are confirmed by means of detailed numerical simulations. Even though the models we consider have trivial equilibrium properties they display a surprising range of dynamic behaviour during aging, which can be directly related to the existence and growth in time of dynamic lengthscales. Well-behaved fluctuation-dissipation ratios can be defined; we confirm in particular the existence of {\em negative} fluctuation-dissipation ratios for a large number of observables. Our results suggest that well-defined violations of fluctuation-dissipation relations, of a purely dynamic origin and unrelated to the thermodynamic concept of an effective temperature, may in general be present in non-equilibrium glassy materials.}, added-at = {2007-06-20T10:16:09.000+0200}, address = {Genova, Italy}, author = {Leonard, S. and Mayer, P. and Sollich, P. and Berthier, L. and Garrahan, J.P.}, biburl = {https://www.bibsonomy.org/bibtex/2afb94ca29f130051fced8250b0f43a72/statphys23}, booktitle = {Abstract Book of the XXIII IUPAP International Conference on Statistical Physics}, editor = {Pietronero, Luciano and Loreto, Vittorio and Zapperi, Stefano}, interhash = {6f7408ed4477a1244f88671860bc54ef}, intrahash = {afb94ca29f130051fced8250b0f43a72}, keywords = {activated constrained dynamics effective fluctuation-dissipation glasses kinetically models ratio statphys23 temperature topic-3}, month = {9-13 July}, timestamp = {2007-06-20T10:16:18.000+0200}, title = {Negative fluctuation-dissipation ratios and activated aging dynamics in kinetically constrained glass models}, url = {http://st23.statphys23.org/webservices/abstract/preview_pop.php?ID_PAPER=379}, year = 2007 }