Single molecules in solids have been considered as an attractive class of solid-state single quantum systems because they can be chemically synthesized to have stable transitions at desired wavelengths. Here, we report and demonstrate single dibenzoterrylene molecules in crystalline anthracene nanosheets as a solid-state platform for delicate photophysics studies and as building blocks of single-photon devices. The nanosheet sample enables studies of single-molecule photophysics at room temperature, including in situ observation of single-molecule insertion-site jump, quantitative measurements of the associated changes of dipole-moment orientation and magnitude, and determination of the excitation-power-dependent intersystem crossing rate and the triplet lifetime. Moreover, we demonstrate the flexible assembly of the nanosheets into a planar Yagi-Uda antenna device to achieve a Gaussian-like angular emission pattern from single dibenzoterrylene molecules. The low thickness (approximately 100 nm), good photostability, and mechanical stability make the dibenzoterrylene-in-anthracene-nanosheet system an excellent candidate for static quantum nodes in integrated photonic circuits.

• Received 5 November 2019
• Revised 21 March 2020
• Accepted 21 May 2020

DOI:https://doi.org/10.1103/PhysRevApplied.13.064023