Cui Qiu Hong, Peng Qian, Luo Yi, Jiang Yuqian, Yan Yongli, Wei Cong, Shuai Zhigang, Sun Cheng, Yao Jiannian, Zhao Yong Sheng
Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
Hefei National Laboratory for Physical Sciences at the Microscale and Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, China.
Sci Adv. 2018 Mar 16;4(3):eaap9861. doi: 10.1126/sciadv.aap9861. eCollection 2018 Mar.
The ability to steer the flow of light toward desired propagation directions is critically important for the realization of key functionalities in optical communication and information processing. Although various schemes have been proposed for this purpose, the lack of capability to incorporate an external electric field to effectively tune the light propagation has severely limited the on-chip integration of photonics and electronics. Because of the noninteractive nature of photons, it is only possible to electrically control the flow of light by modifying the refractive index of materials through the electro-optic effect. However, the weak optical effects need to be strongly amplified for practical applications in high-density photonic integrations. We show a new strategy that takes advantage of the strong exciton-photon coupling in active waveguides to effectively manipulate photon transport by controlling the interaction between excitons and the external electric field. Single-crystal organic semiconductor nanowires were used to generate highly stable Frenkel exciton polaritons with strong binding and diffusion abilities. By making use of directional exciton diffusion in an external electric field, we have realized an electrically driven asymmetric photon transport and thus directional light propagation in a single nanowire. With this new concept, we constructed a dual-output single wire-based device to build an electrically controlled single-pole double-throw optical switch with fast temporal response and high switching frequency. Our findings may lead to the innovation of concepts and device architectures for optical information processing.
将光流引导至所需传播方向的能力对于实现光通信和信息处理中的关键功能至关重要。尽管为此目的已经提出了各种方案，但缺乏结合外部电场以有效调谐光传播的能力严重限制了光子学与电子学的片上集成。由于光子的非相互作用性质，只能通过电光效应改变材料的折射率来电控制光流。然而，对于高密度光子集成中的实际应用，微弱的光学效应需要被强烈放大。我们展示了一种新策略，该策略利用有源波导中强激子 - 光子耦合，通过控制激子与外部电场之间的相互作用来有效操纵光子传输。单晶有机半导体纳米线用于产生具有强束缚和扩散能力的高度稳定的弗伦克尔激子极化激元。通过利用外部电场中的定向激子扩散，我们在单个纳米线中实现了电驱动的不对称光子传输，从而实现了定向光传播。基于这一新概念，我们构建了一种基于单根线的双输出器件，以构建具有快速时间响应和高开关频率的电控单刀双掷光开关。我们的发现可能会引发光信息处理概念和器件架构的创新。
