论文标题
合金中连续过渡的自洽重归其化组方法。申请$β$ brass的订购
Self-consistent renormalization group approach to continuous phase transitions in alloys. Application to ordering in $β$-brass
论文作者
论文摘要
有效培养基类型的自洽（SC）重新归一化组方法已开发并应用于ISING模型（IM）的解决方案。先前用于空间均匀系统的局部电位近似（LPA）中的重新规范化组方程已扩展到晶格案例，并补充了对配对相关函数的自搭配条件。为了验证该方法已应用于简单的立方IM和使用SC-LPA方程计算出的自发磁化的良好一致性，并建立了可用的精确蒙特卡洛模拟数据。接下来，该方法已应用于对应于$β$ brass的BCC IM。通过使用可用的{\ em ab intio}计算有效的对相互作用参数，临界温度，相关长度和临界点附近的远程顺序参数已与实验数据一致。为了支持以下建议：与通用值相比，通过实验观察到的有效关键指数的减少，通过在{\ em ab intib}计算中发现的第二个邻居对相互作用的正值增强了实验观察到的有效关键指数的建议。
A self-consistent (SC) renormalization group approach of the effective medium kind has been developed and applied to the solution of the Ising model (IM). A renormalization group equation in the local potential approximation (LPA) derived previously for spatially homogeneous systems has been extended to the lattice case and supplemented with a self-consistency condition on the pair correlation function. To validate the approach it has been applied to the simple cubic IM and good agreement of the spontaneous magnetization calculated with the use of the SC-LPA equation with the available exact Monte Carlo simulations data has been established. Next the approach has been applied to the bcc IM corresponding to $β$-brass. With the use of the effective pair interaction parameters from available {\em ab initio} calculations the critical temperature, the correlation length and the long range order parameter in the vicinity of the critical point have been calculated in excellent agreement with experimental data. Qualitative and quantitative arguments have been given in support of the suggestion that the experimentally observed decrease of the effective critical exponent of the order parameter in comparison with the universal value is enhanced by the positive value of the second neighbour pair interaction found in the {\em ab initio} calculations.
