Godsi M, Golombek A, Balasubrahmaniyam M, Schwartz T
School of Chemistry, Raymond and Beverly Sackler Faculty of Exact Sciences and Center for Light-Matter Interaction, Tel Aviv University, Tel Aviv 6997801, Israel.
J Chem Phys. 2023 Oct 7;159(13). doi: 10.1063/5.0167945.
Recently, we predicted theoretically that in cavities that support several longitudinal modes, strong coupling can occur in very different manners, depending on the system parameters. Distinct longitudinal cavity modes are either entangled with each other via the material or independently coupled to the exciton mode. Here, we experimentally demonstrate the transition between those two regimes as the cavity thickness is gradually increased while maintaining fixed coupling strength. We study the properties of the system using reflection and emission spectroscopy and show that even though the coupling strength is constant, different behavior in the spectral response is observed along the coupling-decoupling transition. In addition, we find that in such multimode cavities, pronounced upper polariton emission is observed, in contrast to the usual case of a single-mode cavity. Furthermore, we address the ultrafast dynamics of the multimode cavities by pump-probe spectroscopic measurements and observe that the transient spectra significantly change through the transition.
最近，我们从理论上预测，在支持多个纵向模式的腔中，根据系统参数的不同，强耦合会以非常不同的方式发生。不同的纵向腔模式要么通过材料相互纠缠，要么独立地与激子模式耦合。在这里，我们通过实验证明了在保持固定耦合强度的同时，随着腔厚度逐渐增加，这两种状态之间的转变。我们使用反射和发射光谱研究了该系统的特性，并表明尽管耦合强度恒定，但在耦合 - 解耦转变过程中，光谱响应会出现不同的行为。此外，我们发现，与单模腔的通常情况相比，在这种多模腔中观察到了明显的上极化激元发射。此外，我们通过泵浦 - 探测光谱测量研究了多模腔的超快动力学，并观察到瞬态光谱在转变过程中发生了显著变化。
