线性驱动下一级相变的重正化群理论

Renormalization Group Theory of First-Order Phase Transitions under Linear Driving External Field

把重正化群理论应用于一受外场驱动而发生一级相变的系统中，结果表明，与有序化过程一样，该系统也由零温不动点所决定，并得到磁化强度及结构函数的新的动力学标度关系．由此可获得滞后回约面积与变场速率的标度关系．

We apply for the first time renormalization group theory to a system with a first-order phase transition between opposite magnetizations driven linearly by an external magnetic field.The system is described by the large--N model with continuous symmetry and its dynamics is governed by the time-dependent Ginzburg-Landau model. We show explicitly that the driven transition is also governed by the zero-temperature fixed point, and obtain novel dynamic scaling forms for the magnetization and the structure factor. From these relations the scaling form for the area of hysteresis loop with corrections follows naturally. Numerical results agree excellently with the theoretical predictions.