Single-molecule characterization from the perspective of optics, photonics, and optoelectronics: a review

A single molecule is the building block of the material world and the smallest independently stable unit. Exploring single-molecule properties using optical, photonic, and optoelectronic techniques holds great scientific significance in revealing the molecular dynamics, molecular structures, and molecular quantum properties. Nano-optical techniques, such as single-molecule photoluminescence and Raman scattering, not only enable a comprehensive analysis of interactions and conformational dynamics through spectral analysis but also provide unparalleled insights into elucidating the intricate structure of single molecules through atomic-resolution imaging. The research of photonics based on single-molecule electroluminescence has brought new ideas and limitless possibilities to the design and manufacture of photonic information devices. Single-molecule optoelectronics, which leverages photoexcitation to modulate electrical properties, has significant contributions to elucidating charge transport characteristics and optimizing the optoelectronic functions realized by single-molecule devices. Moreover, the optoelectronic characterization based on the interaction of ultrafast optical pulses with single molecules provides unprecedented opportunities for exploring their dynamic behavior and regulation laws on ultrafast time scales. We provide a timely and comprehensive overview of the latest significant advancements pertaining to the optical, photonic, and optoelectronic properties of single molecules, thereby presenting a fresh perspective for research across diverse fields, including single-molecule photophysics and photochemistry.