Aubry Geoffroy J, Bonnet Fabien, Melich Mathieu, Guyon Laurent, Spathis Panayotis, Despetis Florence, Wolf Pierre-Etienne
Université Grenoble Alpes, Institut Néel, F-38042 Grenoble, France and CNRS, Institut Néel, F-38042 Grenoble, France.
Université Montpellier 2, Laboratoire Charles Coulomb UMR 5221, F-34095 Montpellier, France and CNRS, Laboratoire Charles Coulomb UMR 5221, F-34095 Montpellier, France.
Phys Rev Lett. 2014 Aug 22;113(8):085301. doi: 10.1103/PhysRevLett.113.085301. Epub 2014 Aug 21.
High resolution measurements reveal that condensation isotherms of (4)He in high porosity silica aerogel become discontinuous below a critical temperature. We show that this behavior does not correspond to an equilibrium phase transition modified by the disorder induced by the aerogel structure, but to the disorder-driven critical point predicted for the athermal out-of-equilibrium dynamics of the random-field Ising model. Our results evidence the key role of nonequilibrium effects in the phase transitions of disordered systems.
高分辨率测量结果表明，高孔隙率二氧化硅气凝胶中（4）He的冷凝等温线在临界温度以下变得不连续。我们表明，这种行为并不对应于由气凝胶结构引起的无序所改变的平衡相变，而是对应于随机场伊辛模型的无热非平衡动力学所预测的无序驱动临界点。我们的结果证明了非平衡效应在无序系统相变中的关键作用。
