我们研究了p自旋自旋玻璃模型，以了解在p自旋模型的平均场区域中发现的有限温度玻璃转变，并用于模拟结构玻璃的行为，是否在非平均场区域中持续存在。通过使用具有长程幂律稀释相互作用的3自旋自旋玻璃模型，我们能够通过相互作用的指数连续地调整（有效）空间维度。对自旋玻璃磁化率和两点有限尺寸相关长度的蒙特卡罗模拟表明，在非平均场区域的深处，有限温度跃迁丢失，而在平均场区域的情况并非如此，这与Moore和Drossel的预测一致[Phys. Rev. Lett. 89，217202（2002）]，3-自旋模型与磁场中的伊辛自旋玻璃处于相同的普适类。然而，稍微在非平均场区域，我们发现一个明显的过渡，在3自旋模型，在一个字段中的伊辛自旋玻璃的结果相反。这可能表明需要更大的尺寸来探测该区域的渐进行为。
英文摘要：
We study a p-spin spin-glass model to understand if the finite-temperature glass transition found in the mean-field regime of p-spin models, and used to model the behavior of structural glasses, persists in the non-mean-field regime. By using a 3-spin spin-glass model with long-range power-law diluted interactions we are able to continuously tune the (effective) space dimension via the exponent of the interactions. Monte Carlo simulations of the spin-glass susceptibility and the two-point finite-size correlation length show that deep in the non-mean-field regime the finite-temperature transition is lost, whereas this is not the case in the mean-field regime, in agreement with the prediction of Moore and Drossel [Phys. Rev. Lett. 89, 217202 (2002)] that 3-spin models are in the same universality class as an Ising spin glass in a magnetic field. However, slightly in the non-mean-field region, we find an apparent transition in the 3-spin model, in contrast to results for the Ising spin glass in a field. This may indicate that even larger sizes are needed to probe the asymptotic behavior in this region.
The existence of an equilibrium glassy phase for charges in a disordered potential with long-range electrostatic interactions has remained controversial for many years. Here we conduct an extensive numerical study of the disorder-temperature phase diagram of the three-dimensional Coulomb glass model using population annealing Monte Carlo to thermalize the system down to extremely low temperatures. Our results strongly suggest that, in addition to a charge order phase, a transition to a glassy phase can be observed, consistent with previous analytical and experimental studies.
Recent theoretical advances predict the existence, deep into the glass phase, of a novel phase transition, the so-called Gardner transition. This transition is associated with the emergence of a complex free energy landscape composed of many marginally stable sub-basins within a glass metabasin. In this study, we explore several methods to detect numerically the Gardner transition in a simple structural glass former, the infinite-range Mari-Kurchan model. The transition point is robustly located from three independent approaches: (i) the divergence of the characteristic relaxation time, (ii) t…
We study the problem of glassy relaxations in the presence of an external field in the highly controlled context of a spin-glass simulation. We consider a small spin glass in three dimensions (specifically, a lattice of size L=8, small enough to be equilibrated through a Parallel Tempering simulations at low temperatures, deep in the spin glass phase). After equilibrating the sample, an external field is switched on, and the subsequent dynamics is studied. The field turns out to reduce the relaxation time, but huge statistical fluctuations are found when different samples are compared. After t…
The one-dimensional Ising spin-glass model with power-law long-range interactions is a useful proxy model for studying spin glasses in higher space dimensions and for finding the dimension at which the spin-glass state changes from having broken replica symmetry to that of droplet behavior. To this end we have calculated the exponent that describes the difference in free energy between periodic and antiperiodic boundary conditions. Numerical work is done to support some of the assumptions made in the calculations and to determine the behavior of the interface free-energy exponent of the power …
The fractal dimension of excitations in glassy systems gives information on the critical dimension at which the droplet picture of spin glasses changes to a description based on replica symmetry breaking where the interfaces are space filling. Here, the fractal dimension of domain-wall interfaces is studied using the strong-disorder renormalization group method pioneered by Monthus [Fractals 23, 1550042 (2015)] both for the Edwards-Anderson spin-glass model in up to 8 space dimensions, as well as for the one-dimensional long-ranged Ising spin-glass with power-law interactions. Analyzing the fr…
We explore the stability of far-from-equilibrium metastable states of a three-dimensional Coulomb glass at zero temperature by studying charge avalanches triggered by a slowly varying external electric field. Surprisingly, we identify a sharply defined dynamical ("depinning") phase transition from stationary to nonstationary charge displacement at a critical value of the external electric field. Using particle-conserving dynamics, scale-free system-spanning avalanches are observed only at the critical field. We show that the qualitative features of this depinning transition are completely diff…
We consider the long-ranged Ising spin-glass with random couplings decaying as a power-law of the distance, in the region of parameters where the spin-glass phase exists with a positive droplet exponent. For the Metropolis single-spin-flip dynamics near zero temperature, we construct via real-space renormalization the full hierarchy of relaxation times of the master equation for any given realization of the random couplings. We then analyze the probability distribution of dynamical barriers as a function of the spatial scale. This real-space renormalization procedure represents a simple explic…
We present results of a Monte Carlo study of the equilibrium dynamics of the one dimensional long-range Ising spin glass model. By tuning a parameter $σ$, this model interpolates between the mean field Sherrington-Kirkpatrick model and a proxy of the finite dimensional Edward-Anderson model. Activated scaling fits for the behavior of the relaxation time $τ$ as a function of the number of spins $N$ (Namely $\ln(τ)\propto N^ψ$) give values of $ψ$ that are not stable against inclusion of subleading corrections. Critical scaling ($τ\propto N^ρ$) gives more stable fits, at least in the non mean fie…
The relative importance of the contributions of droplet excitations and domain walls on the ordering of short-range Edwards-Anderson spin glasses in three and four dimensions is studied. We compare the overlap distributions of periodic and free boundary conditions using population annealing Monte Carlo. For system sizes up to about 1000 spins, spin glasses show non-trivial spin overlap distributions. Periodic boundary conditions can trap diffusive domain walls which can contribute to small spin overlaps, and the other contribution is the existence of low-energy droplet excitations within the s…
The ground-state properties of quasi-one-dimensional (Q1D) Ising spin glass are investigated using an exact numerical approach and analytical arguments. A set of coupled recursive equations for the ground-state energy are introduced and solved numerically. For various types of coupling distribution, we obtain accurate results for magnetization, particularly in the presence of a weak external magnetic field. We show that in the weak magnetic field limit, similar to the 1D model, magnetization exhibits a singular power-law behavior with divergent susceptibility. Remarkably, the spectrum of magne…
Dynamics of structural models with a long-range interaction: glassy versus non-glassy behavior
利用Langevin动力学及其生成泛函（GF）公式，系统地研究了相互作用的长程性质对玻璃形成趋势的影响。在这样做时，考虑两种类型的模型：（i）具有纯排斥型相互作用的非无序模型和（ii）具有随机分布的相互作用强度的模型（淬火无序模型）。长程相互作用势与粒子数$N$成比例，使得GF的鞍点处理以及系统的1/N - expansion around it. We表明，非无序模型没有玻璃化转变，这与模耦合理论（MCT）预测的平均场极限一致。另一方面，具有长程相互作用的模型，其上具有淬火无序，导致MC -方程，其对于$p$ -自旋玻璃模型和随机介质中的聚合物歧管是通用的。
Glassy Freezing and Long-Range Order in the 3D Random Field $XY$ Model
Monte Carlo研究的三维随机场$XY$模型的简单立方晶格的大小$64^3$，使用两种不同的各向同性随机场的概率分布的中等强度，显示了玻璃冻结行为以上$T_c$，和长程序以下$T_c$，与我们的早期结果较弱和较强的随机场。这个模型应该描述在II型超导合金，电荷密度波材料，和十次对称准晶涡旋晶格的随机钉扎。
As a guideline for experimental tests of the ideal glass transition (Random Pinning Glass Transition, RPGT) that shall be induced in a system by randomly pinning particles, we performed first-principle computations within the Hypernetted chain approximation and numerical simulations of a Hard Sphere model of glass-former. We obtain confirmation of the expected enhancement of glassy behaviour under the procedure of random pinning, which consists in freezing a fraction $c$ of randomly chosen particles in the positions they have in an equilibrium configuration. We present the analytical phase dia…
