2017.12.07 (周四),10:00-11:15,旗山校区理工楼3#303,吕智国,学术讲座【强驱动量子动力学:幺正变换方法】

时间:2017-12-05浏览:576

学术讲座【 强驱动量子动力学:幺正变换方法】

时间:2017.12.07 (周四),10:00-11:15

地点:旗山校区理工实验楼3-303

主讲:吕智国

主办:物理与能源学院、福建省量子调控与新能源材料重点实验室,福建省太阳能转换与储能工程技术研究中心

专家简介: 吕智国,2004年毕业上海交通大学,工作于上海交通大学大学物理教学研究组。研究方向:量子开系统物理和量子相变,先后发表30多篇论文。


报告摘要:
We investigate the dynamics of a driven two-level system (semi-classical Rabi model) using the counter-rotating-hybridized rotating-wave method (CHRW), which is a simple method based on a unitary transformation [1]. After comparing the results of different RWA schemes and those of the numerically exact method in a wide range of parameter regime, we show that the CHRW method gives the accurate driven dynamics which is in good agreement with the numerical method[1-2]. The CHRW method reveals the effects of the CR terms clearly by means of coherent destruction of tunneling, Bloch-Siegert (BS) shift,and fluorescence spectrum. In quantitative comparison with the numerically exact BS shift obtained by Floquet formalism as well as the previous BS results, we confirm that our calculated results are not only accurate in the weak-driving regime but also correct in the strong-driving limit. In the intermediate strong-driving regime, the calculated values of the BS shift are nearly the same as the exact ones. It turns out that our calculation for the BS shift is beyond perturbation. Meanwhile, we demonstrate the signatures caused by the BS shift by monitoring the excited-state population and the probe-pump spectrum under the experiment accessible conditions [3-4].

【1】 Zhiguo Lü, and Hang Zheng, Effects of counterrotating interaction on driven tunneling dynamics: coherent destruction of tunneling and Bloch-Siegert shift, Phys. Rev. A86, 023831(2012).                              
【2】Zhiguo Lü, Yiying Yan, Hsi-Sheng Goan and Hang Zheng, Bias-modulated dynamics of a strongly driven two-level system, Phys. Rev. A93, 033803(2016).

【3】Y. Yan, Zhiguo Lü, and H. Zheng, Bloch-Siegert shift of the Rabi model, Phys. Rev. A91, 053834(2015).

【4】Y. Yan, Zhiguo Lü, and H. Zheng, Effects of counter-rotating-wave terms of the driving field on the spectrum of resona