Chen Lipeng, Yan Yiying, Gelin Maxim F, Lü Zhiguo
Zhejiang Laboratory, Hangzhou 311100, China.
Department of Physics, School of Science, Zhejiang University of Science and Technology, Hangzhou 310023, China.
J Chem Phys. 2023 Mar 14;158(10):104109. doi: 10.1063/5.0138399.
The dynamics of the (sub-)Ohmic spin-boson model under various bath initial conditions is investigated by employing the Dirac-Frenkel time-dependent variational approach with the multiple Davydov D Ansatz in the interaction picture. The validity of our approach is carefully checked by comparing the results with those of the hierarchy equations of motion method. By analyzing the features of nonequilibrium dynamics, we identify the phase diagrams for different bath initial conditions. We find that for the spectral exponent s < s, there exists a transition from coherent to quasicoherent dynamics with increasing coupling strengths. For s < s ≤ 1, the coherent to incoherent crossover occurs at a certain coupling strength and the quasicoherent dynamics emerges at much larger couplings. The initial preparation of the bath has a considerable influence on the dynamics.
通过在相互作用绘景中采用具有多个达维多夫 D 近似的狄拉克 - 弗伦克尔含时变分方法，研究了各种浴场初始条件下（亚）欧姆自旋玻色子模型的动力学。通过将结果与运动方程层次方法的结果进行比较，仔细检验了我们方法的有效性。通过分析非平衡动力学的特征，我们确定了不同浴场初始条件下的相图。我们发现，对于谱指数 s < s，随着耦合强度的增加，存在从相干动力学到准相干动力学的转变。对于 s < s ≤ 1，相干到非相干的转变发生在一定的耦合强度处，并且准相干动力学在大得多的耦合下出现。浴场的初始制备对动力学有相当大的影响。
