Physics Department, Zhejiang University, Hangzhou, Zhejiang 310027, China.
J Chem Phys. 2017 Oct 28;147(16):164112. doi: 10.1063/1.4997669.
Following a recently proposed decomposition technique [C. R. Duan et al., Phys. Rev. B 95, 214308 (2017)], we inspect the zero-temperature spin-boson model for five different cutoff functions of the spectral density. With oscillatory and non-oscillatory exponentially decaying functions to decompose the bath correlation function, the hierarchy equation of motion is reliably extended to each spectral density under our investigation. The predicted spin dynamics is gradually converged with the increase of the hierarchic expansion order and the number of decomposing basis functions. Our systematic study of different cutoff functions expands previous results of the delocalized-localized phase transition with the exponential and sudden cutoffs in the spectral density.
受最近提出的分解技术[C. R. Duan 等人，Phys. Rev. B 95, 214308 (2017)]的启发，我们检验了零温自旋-玻色子模型在五种不同光谱密度截断函数下的性质。通过使用振荡和非振荡的指数衰减函数来分解浴关联函数，我们将运动方程的层次结构可靠地扩展到了我们研究的每个光谱密度。随着层次扩展阶数和分解基函数数量的增加，预测的自旋动力学逐渐收敛。我们对不同截断函数的系统研究扩展了以前在光谱密度中使用指数和突然截断时关于非局域-局域相变的结果。
