Although structural glasses are everyday materials playing an increasing role in modern technological applications [1], the glass transition in itself remains a conundrum. Over the two past decades several experimental breakthroughs have deepened our understanding of glasses. Among them, the developpement of third order non-linear response measurements [3,4,5,6,7] have been instrumental in putting forward new ways of measuring a significantly non-trivial thermodynamic response.
This talk will be devoted to showing how fifth order non-linear responses allows us to infer very strong experimental indications of the existence of a thermodynamic critical point in several archetypical glass formers [2]. Time permitting, various kinds of experimental nonlinear responses will be compared [3,4,5,6,7] with these results, aiming at giving a unified physical picture of the non-linear response in dielectric glass formers.

Acknowledgements

We thank C. Alba-Simionesco, A. Coniglio, P.-M. Déjardin, G. Tarjus, and M. Tarzia for interesting discussions. The work presented here was supported by ERC grant NPRGLASS, by the Labex RTRA grant Aricover, by the Institut des Systèmes Complexes ISC-PIF and by the Deutsche Forschungsgemeinschaft via Research Unit FOR1394.

References

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