Relaxation dynamics of a quantum emitter resonantly coupled to a coherent state of a localized surface plasmon.
Relaxation dynamics of a quantum emitter resonantly coupled to a coherent state of a localized surface plasmon.
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DOI：
10.1039/c4fd00165f
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发表时间：
2015-05
影响因子：
3.4
通讯作者：
K. Nerkararyan;S. Bozhevolnyi
中科院分区：
文献类型：
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作者：
K. Nerkararyan;S. Bozhevolnyi
我们研究了量子偶极发射体（QDE）的弛豫动力学，例如，位于金属纳米颗粒（MNP）附近的分子或量子点，所述金属纳米颗粒（MNP）在QDE辐射跃迁的频率下表现出偶极局域表面等离子体（LSP）共振。一个通用的三能级QDE，这是泵浦与外部激光脉冲，从而进入光学活性激发态，被认为是弱耦合到共振LSP所描述的相干态。结果表明，在QDE-MNP特征弛豫时间远短于自由空间中的QDE弛豫时间，但远长于LSP寿命的条件下，QDE弛豫动力学可以用解析的方法描述，其特征一般为非指数衰减和复杂的瞬态行为.这个弛豫过程的主要物理结果是，发射，主要是由MNP决定，出来了一个相当大的延迟。它还表明，在QDE-MNP系统中的能量耗散是相对较弱的光子发射的概率为10.75，一个数字，而令人惊讶的是，不明确地依赖于金属的吸收特性。大量的QDE-MNP系统参数在我们的分析描述打开了新的可能性，控制量子发射动力学。
We investigate the relaxation dynamics of a quantum dipole emitter (QDE), e.g., a molecule or quantum dot, located near a metal nanoparticle (MNP) exhibiting a dipolar localized surface plasmon (LSP) resonance at the frequency of the QDE radiative transition. A generic three-level QDE, which is pumped with an external laser pulse and thereby brought into an optically active excited state, is considered to be weakly coupled to the resonant LSP described by a coherent state. It is shown that, under the condition of the QDE-MNP characteristic relaxation time being much shorter than that of the QDE in free space but much longer than the LSP lifetime, the QDE relaxation dynamics can be described analytically and feature, in general, non-exponential decay with complicated transient behaviour. The main physical consequence of this relaxation process is that the emission, being largely determined by the MNP, comes out with a substantial delay. It is also shown that energy dissipation in the QDE-MNP system is relatively weak with the probability of the photon emission being ∼0.75, a number which, rather surprisingly, does not explicitly depend on the metal absorption characteristics. A large number of QDE-MNP system parameters in our analytical description open new possibilities for controlling quantum emitter dynamics.