标题： 有机材料中动力学超辐射理论 显示英文标题

标题： Theory of dynamical superradiance in organic materials

摘要： 我们发展了动力学超辐射的理论——即初始激发的发射器集合与单模腔之间的集体能量交换——针对有机材料，其中电子态与振动模式耦合。 我们考虑两种模型来捕捉振动效应：首先，通过 Lindblad 主方程中系统的纯退相位项，将振动视为双能级发射器的马尔可夫浴；其次，通过 Holstein--Tavis--Cummings 哈密顿量直接将振动模式包含在系统中。 通过利用发射器的排列对称性和弱 U(1) 对称性，我们开发了一种数值方法，能够精确求解具有局部耗散的 Tavis-Cummings 模型，最多可达 140 个发射器。 使用精确方法，我们验证了平均场和二阶累积近似，并用它们来描述宏观数量的发射器。 我们分析了平均腔光子数、电子相干性和布洛赫矢量长度的动力学，并表明振动模式耦合的影响超越了简单的退相位。 我们的结果表明，在存在振动模式耦合的情况下，超辐射是可能的；对于负的腔失谐，振动耦合甚至可以增强超辐射。 我们将光子数上升时间相对于腔频率失谐的不对称性识别为这种振动辅助超辐射的实验可探测特征。 显示英文摘要

摘要： We develop the theory of dynamical superradiance -- the collective exchange of energy between an ensemble of initially excited emitters and a single-mode cavity -- for organic materials where electronic states are coupled to vibrational modes. We consider two models to capture the vibrational effects: first, vibrations treated as a Markovian bath for two-level emitters, via a pure dephasing term in the Lindblad master equation for the system; second, vibrational modes directly included in the system via the Holstein--Tavis--Cummings Hamiltonian. By exploiting the permutation symmetry of the emitters and weak U(1) symmetry, we develop a numerical method capable of exactly solving the Tavis-Cummings model with local dissipation for up to 140 emitters. Using the exact method, we validate mean-field and second-order cumulant approximations and use them to describe macroscopic numbers of emitters. We analyse the dynamics of the average cavity photon number, electronic coherence, and Bloch vector length, and show that the effect of vibrational mode coupling goes beyond simple dephasing. Our results show that superradiance is possible in the presence of vibrational mode coupling; for negative cavity detunings, the vibrational coupling may even enhance superradiance. We identify asymmetry of the photon number rise time as a function of the detuning of the cavity frequency as an experimentally accessible signature of such vibrationally assisted superradiance.