近日，中山大学的刘进&王雪华及其研究团队取得一项新进展。经过不懈努力，他们对固态腔量子电动力学中的动态共振荧光进行研究。相关研究成果已于2024年1月10日在国际知名学术期刊《自然—光子学》上发表。
本文报道了在固态腔量子电动力学系统中对Mollow三重态以外的动态共振荧光光谱的直接观察和系统研究。研究发现，动态共振荧光光谱具有多达五对侧峰，并表现出激发失谐诱导的光谱不对称。此外，还观察到了腔滤波效应，并对其进行了定量建模，包括全量子模型声子散射等效应。时间分辨测量进一步表明，多侧峰源于与激发脉冲的不同时间位置相关的发射干涉。这项研究工作为在两能级系统动态驱动下产生各种奇异的光量子态提供了重要依据。
据悉，二能级系统与电磁场之间的相干相互作用是基础量子物理学和现代光子量子技术的重要基础。一个典型的例子是共振荧光现象，当一个二能级系统受到谐振激光的连续驱动时，会发出非经典光子，形成Mollow三重态。通过使用短光脉冲将共振荧光从静态推向动态状态，可以产生高相干性的单光子按需发射。当进一步增加动力系统的驱动强度时，可以实现光子数叠加态、光子数纠缠态和光子束态等奇特的非经典光发射。尽管人们一直渴望观察到Mollow三重态以外的光谱特征，即在强驱动强度下的动态共振荧光特性，但这一目标尚未实现。
附：英文原文
Title: Dynamic resonance fluorescence in solid-state cavity quantum electrodynamics
Author: Liu, Shunfa, Gustin, Chris, Liu, Hanqing, Li, Xueshi, Yu, Ying, Ni, Haiqiao, Niu, Zhichuan, Hughes, Stephen, Wang, Xuehua, Liu, Jin
Issue&Volume: 2024-01-10
Abstract: The coherent interaction between a two-level system and electromagnetic fields serves as a foundation for fundamental quantum physics and modern photonic quantum technology. A profound example is resonance fluorescence, where the non-classical photon emission appears in the form of a Mollow-triplet when a two-level system is continuously driven by a resonant laser. Pushing resonance fluorescence from a static to dynamic regime by using short optical pulses generates on-demand emissions of highly coherent single photons. Further increasing the driving strength in the dynamical regime enables the pursuit of exotic non-classical light emission in photon number superposition, photon number entanglement and photon bundle states. However, the long-sought-after spectrum beyond the Mollow-triplet, a characteristic of dynamic resonance fluorescence under strong driving strength, has not yet been observed. Here we report the direct observation and systematic investigations of dynamic resonance fluorescence spectra beyond the Mollow-triplet in a solid-state cavity quantum electrodynamic system. The dynamic resonance fluorescence spectra—with up to five pairs of side peaks, excitation detuning-induced spectral asymmetry, and cavity filtering effects—are observed and quantitatively modelled by a full-quantum model with phonon scattering included. Time-resolved measurements further reveal that the multiple side peaks originate from interference of the emission associated with different temporal positions of the excitation pulses. Our work facilitates the generation of a variety of exotic quantum states of light with dynamic driving of two-level systems.
DOI: 10.1038/s41566-023-01359-x
Source: https://www.nature.com/articles/s41566-023-01359-x