Matching Microscopic and Macroscopic Responses in Glasses
· Invited
Abstract
We use Janus and Janus II supercomputers to revisit two successful experimental approaches to detect the glass correlation length from macroscopic observables [1]. On the one hand, we reproduce a milestone experiment to measure spin-glass coherence length, ξmax, through the lowering of free-energy barriers induced by the Zeeman effect [2], and on the other hand, we explore the relationship between the spin-glass coherence length and the macroscopic non-linear susceptibilities, the latter recently measured in supercooled glasses [3] to support the existence of a growth of thermodynamic amorphous order upon approaching the ideal glass transition. We compare these macroscopic measures, with the microscopic spin-glass coherence length ξmic (as extracted from the four-point spatial correlation function), concluding that (i) ξmax and ξmic are mutually consistent, and (ii) the non-linear susceptibilities scale as powers of ξmic, so they can be used to describe the growth of an amorphous order in glass formers. In addition, we propose scaling laws on the applied field that have allowed a quantitative analysis of new experiments [4].
[1] Janus Collaboration, Phys. Rev. Lett. 118, 157202 (2017).
[2] Y. G. Joh, R. Orbach, G. G. Wood, J. Hammann, and
E. Vincent, Phys. Rev. Lett. 82, 438 (1999).
[3] S. Albert, T. Bauer, M. Michl, G. Biroli, J.-P. Bouchaud,
A. Loidl, P. Lunkenheimer, R. Tourbot, C. WiertelGasquet,
and F. Ladieu, Science 352, 1308 (2016).
[4] S. Guchhait and R. Orbach, Phys. Rev. Lett. 118, 157203 (2017).
[1] Janus Collaboration, Phys. Rev. Lett. 118, 157202 (2017).
[2] Y. G. Joh, R. Orbach, G. G. Wood, J. Hammann, and
E. Vincent, Phys. Rev. Lett. 82, 438 (1999).
[3] S. Albert, T. Bauer, M. Michl, G. Biroli, J.-P. Bouchaud,
A. Loidl, P. Lunkenheimer, R. Tourbot, C. WiertelGasquet,
and F. Ladieu, Science 352, 1308 (2016).
[4] S. Guchhait and R. Orbach, Phys. Rev. Lett. 118, 157203 (2017).
*The computers Janus and Janus II, custom-built for the simulation of spin glasses, have been constructed by the Janus Collaboration, a consortium of researchers from Spain (U. Zaragoza, U. Complutense and U. Extremadura) and Italy (La Sapienza, U. di Roma and U. Ferrara).
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Presenters
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Beatriz Seoane
- Ecole Normale
- Laboratoire de Physique Théorique, Ecole Normale Superieure