Franz Silvio, Maimbourg Thibaud, Parisi Giorgio, Scardicchio Antonello
Laboratoire de Physique Théorique et Modèles Statistiques, CNRS, Université Paris-Sud, Université Paris-Saclay, 91405 Orsay, France.
Condensed Matter and Statistical Physics Section, The Abdus Salam International Centre for Theoretical Physics, 34151 Trieste, Italy;
Proc Natl Acad Sci U S A. 2019 Jul 9;116(28):13768-13773. doi: 10.1073/pnas.1820360116. Epub 2019 Jun 24.
We present a mechanism for the anomalous behavior of the specific heat in low-temperature amorphous solids. The analytic solution of a mean-field model belonging to the same universality class as high-dimensional glasses, the spherical perceptron, suggests that there exists a cross-over temperature above which the specific heat scales linearly with temperature, while below it, a cubic scaling is displayed. This relies on two crucial features of the phase diagram: () the marginal stability of the free-energy landscape, which induces a gapless phase responsible for the emergence of a power-law scaling; and () the vicinity of the classical jamming critical point, as the cross-over temperature gets lowered when approaching it. This scenario arises from a direct study of the thermodynamics of the system in the quantum regime, where we show that, contrary to crystals, the Debye approximation does not hold.
我们提出了一种关于低温非晶态固体中比热异常行为的机制。一个与高维玻璃属于同一普适类的平均场模型——球形感知器的解析解表明,存在一个交叉温度,高于此温度时比热随温度线性变化,而低于此温度时则呈现立方标度。这依赖于相图的两个关键特征:()自由能景观的边缘稳定性,它导致了一个无隙相,该相是幂律标度出现的原因;以及()经典堵塞临界点的临近,因为当接近它时交叉温度会降低。这种情况源于对量子 regime 中系统热力学的直接研究,我们在其中表明,与晶体不同,德拜近似不成立。