Fifth-order susceptibility unveils growth of thermodynamic amorphous order in glass-formers.
Glasses are ubiquitous in daily life and technology. However, the microscopic mechanisms generating this state of matter remain subject to debate: Glasses are considered either as merely hyperviscous liquids or as resulting from a genuine thermodynamic phase transition toward a rigid state. We show that third- and fifth-order susceptibilities provide a definite answer to this long-standing controversy. Performing the corresponding high-precision nonlinear dielectric experiments for supercooled glycerol and propylene carbonate, we find strong support for theories based on thermodynamic amorphous order. Moreover, when lowering temperature, we find that the growing transient domains are compact--that is, their fractal dimension d(f) = 3. The glass transition may thus represent a class of critical phenomena different from canonical second-order phase transitions for which d(f) < 3.
SPEC, CEA, CNRS, Université Paris-Saclay, CEA Saclay Bat 772, 91191 Gif-sur-Yvette Cedex, France.
S
S
Albert
Experimental Physics V, Center for Electronic Correlations and Magnetism, University of Augsburg, 86159 Augsburg, Germany.
Th
T
Bauer
Experimental Physics V, Center for Electronic Correlations and Magnetism, University of Augsburg, 86159 Augsburg, Germany.
M
M
Michl
IPhT, CEA, CNRS, Université Paris-Saclay, CEA Saclay Bat 774, 91191 Gif-sur-Yvette Cedex, France. LPS, Ecole Normale Supérieure, 24 rue Lhomond, 75231 Paris Cedex 05, France.
G
G
Biroli
Capital Fund Management, 23 rue de l'Université, 75007 Paris, France.
J-P
JP
Bouchaud
Experimental Physics V, Center for Electronic Correlations and Magnetism, University of Augsburg, 86159 Augsburg, Germany.
A
A
Loidl
Experimental Physics V, Center for Electronic Correlations and Magnetism, University of Augsburg, 86159 Augsburg, Germany.
P
P
Lunkenheimer
SPEC, CEA, CNRS, Université Paris-Saclay, CEA Saclay Bat 772, 91191 Gif-sur-Yvette Cedex, France.
R
R
Tourbot
SPEC, CEA, CNRS, Université Paris-Saclay, CEA Saclay Bat 772, 91191 Gif-sur-Yvette Cedex, France.
C
C
Wiertel-Gasquet
SPEC, CEA, CNRS, Université Paris-Saclay, CEA Saclay Bat 772, 91191 Gif-sur-Yvette Cedex, France. francois.ladieu@cea.fr.
F
F
Ladieu