论文标题
非热踢转子模型中的动力稳定性
Dynamical stability in a non-Hermitian kicked rotor model
论文作者
论文摘要
我们研究了非踢脚的转子模型中的量子不可逆性和量子扩散，踢脚强度很复杂。我们的结果表明，洛斯米特回声的指数衰减逐渐消失，随着非富甲驱动潜力的虚构部分的强度，这表明了非热性抑制了指数的不稳定性。量子扩散在动量空间中表现出动力学定位，即，动量的平方平方随时间演化而增加至饱和，这随着踢球的想象部分的强度的增加而降低。这清楚地揭示了通过非热性增强动力学定位的增强。在分析和数字上，我们发现量子状态主要在少数的quasieigenstates上填充，具有明显的假想部分准元素。有趣的是，偏元状态的反参与率的平均值随踢势假想部分的强度的增加而降低，这意味着quasieigenstates的特征决定了波袋动力学的稳定性以及能量扩散的动力学位置。
We investigate the quantum irreversibility and quantum diffusion in a non-Hermitian kicked rotor model for which the kicking strength is complex. Our results show that the exponential decay of Loschmidt echo gradually disappears with increasing the strength of the imaginary part of non-Hermitian driven potential, demonstrating the suppress of the exponential instability by non-Hermiticity. The quantum diffusion exhibits the dynamical localization in momentum space, namely, the mean square of momentum increases to saturation with time evolution, which decreases with the increase of the strength of the imaginary part of the kicking. This clearly reveals the enhancement of dynamical localization by non-Hermiticity. We find, both analytically and numerically, that the quantum state are mainly populated on a very few quasieigenstates with significantly large value of the imaginary part of quasienergies. Interestingly, the average value of the inverse participation ratio of quasieigenstates decreases with the increase of the strength of the imaginary part of the kicking potential, which implies that the feature of quasieigenstates determines the stability of wavepacket's dynamics and the dynamical localization of energy diffusion.
