Department of Physics, Chalmers University of Technology, SE-412 96 Gothenburg, Sweden.
Institut für Theoretische Physik, Nichtlineare Optik und Quantenelektronik, Technische Universität Berlin, Hardenbergstraße 36, 10623 Berlin, Germany.
Nat Commun. 2017 Mar 15;8:14776. doi: 10.1038/ncomms14776.
The rapidly increasing use of sensors throughout different research disciplines and the demand for more efficient devices with less power consumption depends critically on the emergence of new sensor materials and novel sensor concepts. Atomically thin transition metal dichalcogenides have a huge potential for sensor development within a wide range of applications. Their optimal surface-to-volume ratio combined with strong light-matter interaction results in a high sensitivity to changes in their surroundings. Here, we present a highly efficient sensing mechanism to detect molecules based on dark excitons in these materials. We show that the presence of molecules with a dipole moment transforms dark states into bright excitons, resulting in an additional pronounced peak in easy accessible optical spectra. This effect exhibits a huge potential for sensor applications, since it offers an unambiguous optical fingerprint for the detection of molecules-in contrast to common sensing schemes relying on small peak shifts and intensity changes.
传感器在不同研究领域的应用迅速增加，对具有更低功耗的更高效设备的需求也在不断增长，这都严重依赖于新型传感器材料和新颖的传感器概念的出现。原子层厚的过渡金属二卤化物在广泛的应用中具有巨大的传感器开发潜力。它们具有最佳的表面积与体积比，再加上强烈的光物质相互作用，使它们对周围环境的变化具有很高的灵敏度。在这里，我们提出了一种基于这些材料中暗激子的高效分子检测传感机制。我们表明，具有偶极矩的分子的存在将暗态转化为亮激子，从而在易于获取的光学光谱中产生额外的显著峰。与依赖于小峰位移和强度变化的常见传感方案相比，这种效应为传感器应用提供了巨大的潜力，因为它为分子检测提供了一个明确的光学指纹。
