Isothermal remanent magnetization and the spin dimensionality of spin glasses

Absence of aging in the remanent magnetization in Migdal-Kadanoff spin glasses

We study the non-equilibrium behavior of three-dimensional spin glasses in the Migdal-Kadanoff approximation, that is on a hierarchical lattice. In this approximation the model has an unique ground state and equilibrium properties correctly described by the droplet model. Extensive numerical simulations show that this model lacks aging in the remanent magnetization as well as a maximum in the magnetic viscosity in disagreement with experiments as well as with numerical studies of the Edwards-Anderson model. This result strongly limits the validity of the droplet model (at least in its simplest…

Magnetic Field Scaling in Spin Glasses and the Mean-Field Theory

The scaling of the magnetic field dependence of the remanent magnetization for different temperatures and different spin-glass samples is studied. Particular attention is paid to the effect of the de Almeida-Thouless (AT) critical line on spin-glass dynamics. It is shown that results of the mean-field theory of aging phenomena, with two additional experimentally justified assumptions, predict $H/H_{AT}(T)$ scaling for remanent magnetization curves. Experiments on a single crystal Cu:Mn 1.5 at % sample in the temperature interval from $0.7T_{g}$ to $0.85T_{g}$ give results consistent with this …

Domain growth by isothermal aging in 3d Ising and Heisenberg spin glasses

Non-equilibrium dynamics of three dimensional model spin glasses - the Ising system Fe$_{0.50}$Mn$_{0.50}$TiO$_3$ and the Heisenberg like system Ag(11 at% Mn) - has been investigated by measurements of the isothermal time decay of the low frequency ac-susceptibility after a quench from the paramagnetic to the spin glass phase. It is found that the relaxation data measured at different temperatures can be scaled according to predictions from the droplet scaling model, provided that critical fluctuations are accounted for in the analyzes.

常规与高熵金属玻璃中的非等温应力松弛及其与混合熵和过量熵的关系

Non-isothermal stress relaxation in conventional and high-entropy metallic glasses and its relationship to themixing and excess entropy

本研究通过量热和扭转应力松弛实验，发现高熵金属玻璃（ΔSmix>1.5R）抗应力松弛能力更强，并引入熵基参数ΔS揭示应力松弛深度与混合熵和过量熵的关系。

Metastable States in Spin Glasses and Disordered Ferromagnets

We study analytically M-spin-flip stable states in disordered short-ranged Ising models (spin glasses and ferromagnets) in all dimensions and for all M. Our approach is primarily dynamical and is based on the convergence of a zero-temperature dynamical process with flips of lattice animals up to size M and starting from a deep quench, to a metastable limit. The results (rigorous and nonrigorous, in infinite and finite volumes) concern many aspects of metastable states: their numbers, basins of attraction, energy densities, overlaps, remanent magnetizations and relations to thermodynamic states…

等温退火过程中气相沉积玻璃回春的初始阶段：实验与模拟的对比

Initial Stages of Rejuvenation of Vapor-Deposited Glasses during Isothermal Annealing: Contrast Between Experiment and Simulation

本研究通过介电谱实验观测不同稳定性的气相沉积MMT玻璃的等温回春过程，发现高稳定性玻璃短期退火会引发高频弛豫回春，而swap Monte Carlo算法模拟的高稳定性玻璃在相同时长内无回春迹象，揭示了实验与模拟的差异。