Longhi Stefano
Opt Lett. 2020 Jun 1;45(11):3017-3020. doi: 10.1364/OL.393578.
Spontaneous emission of an excited atom in a featureless continuum of electromagnetic modes is a fundamental process in quantum electrodynamics associated with an exponential decay of the quantum emitter to its ground state accompanied by an irreversible emission of a photon. However, such a simple scenario is deeply modified when considering a "giant" atom, i.e., an atom whose dimension is larger than the wavelength of the emitted photon. In such an unconventional regime, non-Markovian effects and strong deviations from an exponential decay are observed owing to interference effects arising from nonlocal light-atom coupling. Here we suggest a photonic simulation of non-Markovian giant atom decay, based on light escape dynamics in an optical waveguide nonlocally coupled to a waveguide lattice. Major effects, such as nonexponential decay, enhancement, or slowing down of the decay, and formation of atom-field dark states can be emulated in this system.
处于无特征电磁模式连续统中的激发原子的自发辐射是量子电动力学中的一个基本过程，它伴随着量子发射体向其基态的指数衰减以及光子的不可逆发射。然而，当考虑一个“巨型”原子时，即一个尺寸大于所发射光子波长的原子，这种简单的情况会被深刻改变。在这种非传统的情况下，由于非局部光-原子耦合产生的干涉效应，会观察到非马尔可夫效应以及与指数衰减的强烈偏差。在此，我们基于与波导晶格非局部耦合的光波导中的光逃逸动力学，提出一种非马尔可夫巨型原子衰变的光子模拟。在这个系统中，可以模拟诸如非指数衰减、衰减增强或减慢以及原子-场暗态的形成等主要效应。
