We propose an approach for computing the Gibbs free energy difference between phases of a material. The method is based on the determination of the average force acting on interfaces that separate the two phases of interest. This force, which depends on the Gibbs free energy difference between the phases, is computed by applying an external harmonic field that couples to a parameter which specifies the two phases. Validated first for the Lennard-Jones model, we demonstrate the flexibility, efficiency and practical applicability of this approach by computing the melting temperatures of sodium, magnesium, aluminum and silicon at ambient pressure using density functional theory. Excellent agreement with experiment is found for all four elements, except for silicon, for which the melting temperature is, in agreement with previous simulations, seriously underestimated.
The existence of a depinning transition for a high dimensional interface in a weakly disordered medium is controversial. Following Larkin arguments and a perturbative expansion, one expects a linear response with a renormalized mobility $μ_{\text{eff}}$ . In this paper, we compare these predictions with the exact solution of a fully connected model, which displays a finite critical force $f_c$. At small disorder, we unveil an intermediary linear regime for $f_c < f < 1$ characterized by the renormalized mobility $μ_{\text{eff}}$. Our results suggest that in high dimension the critical force is…
Field-controlled interfacial transport and pinning in an active spin system
Wenzhou Institute of the University of Chinese Academy of Sciences（中国科学院大学温州研究院）；School of Physical Sciences, University of Chinese Academy of Sciences（中国科学院大学物理科学学院）；Departament de Física de la Matèria Condensada, Universitat de Barcelona（巴塞罗那大学凝聚态物理学系）；Center for Biophysics & Department for Theoretical Physics, Saarland University（萨尔兰大学生物物理中心与理论物理系）；Laboratoire de Physique Théorique et Modélisation, UMR 8089, CY Cergy Paris Université（CY塞吉巴黎大学理论与建模物理实验室）；School of Mathematical & Computational Sciences, Indian Association for the Cultivation of Science（印度科学培养协会数学与计算科学学院）
Hard-spin mean-field theory has recently been applied to Ising magnets, correctly yielding the absence and presence of an interface roughening transition respectively in $d=2$ and $d=3$ dimensions and producing the ordering-roughening phase diagram for isotropic and anisotropic systems. The approach has now been extended to the effects of quenched random pinning centers and missing bonds on the interface of isotropic and anisotropic Ising models in $d=3$. We find that these frozen impurities cause domain boundary roughening that exhibits consecutive thresholding transitions as a function inter…
We study complete wetting of solid walls that are patterned by parallel nanogrooves of depth $D$ and width $L$ with a periodicity of $2L$. The wall is formed of a material which interacts with the fluid via a long-range potential and exhibits first-order wetting transition at temperature $T_w$, should the wall is planar. Using a non-local density functional theory we show that at a fixed temperature $T>T_w$ the process of complete wetting depends sensitively on two microscopic length-scales $L_c^+$ and $L_c^-$. If the corrugation parameter $L$ is greater than $L_c^+$, the process is continuous…
Interface fluctuations in disordered systems: Universality and non-Gaussian statistics
我们采用了一个功能重整化群来研究在$d=4-ε$尺寸的钉扎电位的存在下的接口。与以前的方法相反[D. S. Fisher，Phys. Rev. Lett. { \bf 56}，1964（1986）]我们使用软截止方案。用这里开发的方法，我们确认的值的粗糙度指数$ζ\approx 0.2083 ε$顺序$ε$。超越以前的工作，我们证明了这个指数是普遍的。此外，我们分析了在无序分布和温度作为一个危险的无关变量的作用，产生更高的累积量。
Quantized topological invariant of symmetry-projected Gibbs states
Hong Kong University of Science and Technology（香港科技大学）；Department of Physics, Hong Kong University of Science and Technology（香港科技大学物理系）；Center for Theoretical Condensed Matter Physics, Hong Kong University of Science and Technology（香港科技大学理论凝聚态物理中心）；Institute for Advanced Study, Hong Kong University of Science and Technology（香港科技大学高等研究院）
