上转换发光量子点

Photon upconversion(UC), a nonlinear optical process that converts multiple low-energy photons into a single high-energy photon, is of significant importance in many fields, such as laser, display, photovoltaic, information security, bioimaging and diagnosis. In compare with the well developed lanthanide-doped nanocrystals and triple-triple annihilation, UC quantum dots can achieve UC luminescence under a wide spectral excitation range, which are emerging as promising candidates for many photonic applications due to their wide spectral absorption, high luminous efficiency, near-infrared absorption, tunable energy band, small size and high stability. In this short review, we summarize the progress of upconversion semiconductor quantum dots with the description of basic mechanisms, recent progress of different types of UC quantum dots, especially UC dual quantum dots that based on excited state absorption, discuss the application potential of UC quantum dots in light-emitting diodes, detectors, solar cells and biomarkers, then we conclude with a brief prespective about the challenges and future prospects in this field.