Abstract

We study by means of the 2D Blume–Emery–Griffiths (BEG) spin-1 model, spin-crossover (SCO) and prussian blue analogs (PBAs) solids. In this model, the spin states, which can be high-spin (HS) or low-spin (LS), interact magnetically and elastically with their nearest neighbors. To account for the volume change, accompanying the spin transition phenomenon, all interactions through the lattice are assumed as temperature-dependent. In addition, the system is subject to a variable magnetic field lifting the degeneracy in the HS state. A stochastic cooperative dynamics of this BEG-like Hamiltonian, describing the equilibrium and nonequilibrium properties of ferromagnetic spin-crossover solids, is derived from the Glauber approach, with appropriate Arrhenius microscopic transition rates. The model generates under the magnetic field, sigmoidal relaxation and a hysteresis phenomenon of the HS fraction, as well as multistep behavior of the magnetization. These behaviors open the way to new route of multi-stable systems, desired in multi-byte electronics.

Graphic Abstract

中文翻译：

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BEG模型中铁磁自旋交叉固体中的磁场诱导的多步跃迁

摘要

我们通过2D Blume-Emery-Griffiths（BEG）spin-1模型，自旋交叉（SCO）和普鲁士蓝类似物（PBA）固体进行研究。在此模型中，自旋态可以是高自旋（HS）或低自旋（LS），并与其最近的邻居发生磁性和弹性相互作用。为了解决伴随自旋跃迁现象的体积变化，通过晶格的所有相互作用均假定为温度依赖性。另外，系统受到可变磁场的影响，从而提升了HS状态下的简并性。这种类似于BEG的哈密顿量的随机合作动力学，描述了铁磁自旋交越固体的平衡和非平衡性质，是由Glauber方法得出的，具有适当的Arrhenius微观转变速率。模型在磁场下产生，乙状结肠松弛和HS分数的磁滞现象，以及磁化的多步行为。这些行为为多字节电子学中需要的多稳定系统的新途径开辟了道路。

图形摘要