Quantum dynamics of a driven two-level molecule with variable dephasing
Quantum dynamics of a driven two-level molecule with variable dephasing
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DOI：
10.1103/physreva.94.063839
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发表时间：
2016-12-19
影响因子：
2.9
通讯作者：
Hinds, E. A.
中科院分区：
文献类型：
--
作者：
Grandi, Samuele;Major, Kyle D.;Hinds, E. A.
二能级量子系统的纵向(Gamma(1))衰减率和横向(Gamma(2))衰减率对其演化有着深刻的影响。具有Gamma(2)=1/2 Gamma(1)的原子系统已被广泛研究，但随着固体量子器件的兴起，考虑由于与固体环境的相互作用而产生的更强的横向弛豫效应也是重要的。在这里，我们研究了单个有机染料分子在激光驱动下的量子动力学。我们测量了伽玛(2)随温度的变化，并确定了光学偶极子热退相的激活能。然后，我们测量了分子发出的光的二阶关联函数g((2))(Tau)随不同的比值Gamma(2)/Gamma(1)和饱和参数s。我们表明光学Bloch方程的通解在这些参数的很大范围内精确地描述了观测到的量子动力学，并讨论了文献中出现的各种g((2))(Tau)近似表达式的局限性。
The longitudinal (Gamma(1)) and transverse (Gamma(2)) decay rates of a two-level quantum system have a profound influence on its evolution. Atomic systems with Gamma(2) = 1/2 Gamma(1) have been studied extensively, but with the rise of solid-state quantum devices it is also important to consider the effect of stronger transverse relaxation due to interactions with the solid environment. Here we study the quantum dynamics of a single organic dye molecule driven by a laser. We measure the variation of Gamma(2) with temperature and determine the activation energy for thermal dephasing of the optical dipole. Then we measure the second-order correlation function g((2))(tau) of the light emitted by the molecule for various ratios Gamma(2)/ Gamma(1) and saturation parameters S. We show that the general solution to the optical Bloch equations accurately describes the observed quantum dynamics over a wide range of these parameters, and we discuss the limitations of the various approximate expressions for g((2))(tau) that appear in the literature.