Gonzalez-Ballestero Carlos, Feist Johannes, Gonzalo Badía Eduardo, Moreno Esteban, Garcia-Vidal Francisco J
Departamento de Física Teórica de la Materia Condensada and Condensed Matter Physics Center (IFIMAC), Universidad Autónoma de Madrid, E-28049 Madrid, Spain.
Donostia International Physics Center (DIPC), E-20018 Donostia/San Sebastián, Spain.
Phys Rev Lett. 2016 Oct 7;117(15):156402. doi: 10.1103/PhysRevLett.117.156402.
When a collection of quantum emitters interacts with an electromagnetic field, the whole system can enter into the collective strong coupling regime in which hybrid light-matter states, i.e., polaritons can be created. Only a small portion of excitations in the emitters are coupled to the light field, and there are many dark states that, in principle, retain their pure excitonic nature. Here we theoretically demonstrate that these dark states can have a delocalized character, which is inherent to polaritons, despite the fact that they do not have a photonic component. This unexpected behavior only appears when the electromagnetic field displays a discrete spectrum. In this case, when the main loss mechanism in the hybrid system stems from the radiative losses of the light field, dark states are even more efficient than polaritons in transferring excitations across the structure.
当一组量子发射体与电磁场相互作用时，整个系统可以进入集体强耦合状态，在这种状态下可以产生混合光物质态，即极化激元。发射体中只有一小部分激发与光场耦合，并且存在许多暗态，原则上这些暗态保留其纯激子性质。在这里，我们从理论上证明，尽管这些暗态没有光子成分，但它们可以具有极化激元固有的离域特性。这种意外行为仅在电磁场呈现离散光谱时出现。在这种情况下，当混合系统中的主要损耗机制源于光场的辐射损耗时，暗态在整个结构中转移激发方面甚至比极化激元更有效。
