噪声对均质形核过程影响的晶体相场法研究

Phase field crystal model for the effect of colored noise on homogenerous nucleation

采用晶体相场模型,模拟了有色噪声诱发的均质形核过程.结果表明,噪声强度在一定范围内对系统平衡热力学参量、形核势垒、临界晶核尺寸影响甚微;而对形核孕育时间影响较大,形核孕育时间随噪声强度的增大呈指数减小趋势.进一步分析表明,噪声对形核孕育时间的影响主要是由于噪声的引入改变了原子动力学系数.

Homogenerous nucleation process induced by the colored noise is simulated by the phase field crystal method.The results indicate that the noise strenghth within a certain range almost has no influence on the parameters of equilibrium thermodynamics of the nucleation system,such as nucleation engergy barrier and size of crtical nucleus;however,it will strongly affect the dynamics of the system.The incubation time of nucleation decreases exponenially with the increase of the noise strength.Further analysis shows that this is attributed to the fact that the colored noise can affect the atom mobility in the nucleation process.