Photonic sensors that are able to detect and track biochemical molecules offer powerful tools for information acquisition in applications ranging from environmental analysis to medical diagnosis. The ultimate aim of biochemical sensing is to achieve both quantitative sensitivity and selectivity. As atomically thick films with remarkable optoelectronic tunability, graphene and its derived materials have shown unique potential as a chemically tunable platform for sensing, thus enabling significant performance enhancement, versatile functionalization and flexible device integration. Here, we demonstrate a partially reduced graphene oxide (prGO) inner-coated and fiber-calibrated Fabry-Perot dye resonator for biochemical detection. Versatile functionalization in the prGO film enables the intracavity fluorescent resonance energy transfer (FRET) to be chemically selective in the visible band. Moreover, by measuring the intermode interference via noise canceled beat notes and locked-in heterodyne detection with Hz-level precision, we achieved individual molecule sensitivity for dopamine, nicotine and single-strand DNA detection. This work combines atomic-layer nanoscience and high-resolution optoelectronics, providing a way toward high-performance biochemical sensors and systems.

能够检测和跟踪生化分子的光子传感器为从环境分析到医学诊断的应用程序中的信息获取提供了强大的工具。生化感测的最终目的是实现定量灵敏度和选择性。作为具有出色的光电可调性的原子厚膜，石墨烯及其衍生材料已显示出独特的潜力，可作为化学可调性的传感平台，从而实现显着的性能增强，多功能的功能化和灵活的器件集成。在这里，我们演示了部分还原的氧化石墨烯（prGO）内涂层和纤维校准的Fabry-Perot染料共振器，用于生化检测。prGO膜中的多功能功能化使腔内荧光共振能量转移（FRET）在可见带中具有化学选择性。此外，通过以消除噪音的拍子音和锁定外差检测（Hz级精度）来测量模式间干扰，我们获得了对多巴胺，尼古丁和单链DNA检测的单个分子灵敏度。这项工作结合了原子层纳米科学和高分辨率光电技术，为高性能生化传感器和系统的开发提供了一种途径。