Institute for Theoretical Physics, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands.
Institute of Physics, EPFL, CH-1015 Lausanne, Switzerland.
Phys Rev E. 2019 Jan;99(1-1):012106. doi: 10.1103/PhysRevE.99.012106.
We present a model and protocol that enable the generation of extremely stable computer glasses at minimal computational cost. The protocol consists of an instantaneous quench in an augmented potential energy landscape, with particle radii as additional degrees of freedom. We demonstrate how our glasses' mechanical stability, which is readily tunable in our approach, is reflected in both microscopic and macroscopic observables. Our observations indicate that the stability of our computer glasses is at least comparable to that of computer glasses generated by the celebrated Swap Monte Carlo algorithm. Strikingly, some key properties support even qualitatively enhanced stability in our scheme: the density of quasilocalized excitations displays a gap in our most stable computer glasses, whose magnitude scales with the polydispersity of the particles. We explain this observation, which is consistent with the lack of plasticity we observe at small stress. It also suggests that these glasses are depleted from two-level systems, similarly to experimental vapor-deposited ultrastable glasses.
我们提出了一种模型和方案,能够以最小的计算成本生成极其稳定的计算机玻璃。该方案由在增强势能景观中的瞬时淬火组成,其中粒子半径作为附加自由度。我们展示了我们的玻璃的机械稳定性如何在微观和宏观可观测物中得到体现,我们的方法可以轻松地调节这种稳定性。我们的观察表明,我们的计算机玻璃的稳定性至少与著名的 Swap 蒙特卡罗算法生成的计算机玻璃相当。值得注意的是,一些关键性质甚至支持我们方案中稳定性的定性增强:准局域激发的密度在我们最稳定的计算机玻璃中显示出一个间隙,其大小与粒子的多分散性成正比。我们解释了这一观察结果,这与我们在小应力下观察到的缺乏塑性一致。这也表明这些玻璃与实验气相沉积的超稳定玻璃一样,耗尽了双稳态系统。