2020/08/15 by Monami Das Modak, Ganesh Damarla, Modak, Monami Das +10
Engineering · Materials Science · #Applied Physics (physics.app-ph) #Chemical Physics (physics.chem-ph) #FOS: Physical sciences #Glass properties and applications #Luminescence Properties of Advanced Materials #Perovskite Materials and Applications #Quantum Dots Synthesis And Properties #Solid State Laser Technologies
paper · pdf · doi:10.48550/arxiv.2008.06783
openalex publication_date 2020/08/15 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
In this work, dot-sized upconversion nanocrystals (UCN-dots) with diameter\nc.a. 3.4-0.15 nm have been synthesized. These UCN-dots exhibit visible emission\n(at 497, 527 and 545 nm) under the excitation with 980 nm CW-NIR laser.\nFurther, these UCN-dots exhibit high energy upconversion emission (UV region,\n206 to 231 nm) with Ti-Sapphire Femtosecond laser of 140-femtoseconds duration\nat 80 MHz repetition rate at different excitation, which has never been\nreported. This is interesting to report that the generation of high energy\nUV-Vis emission and their shifting from 206 to 231 nm for the UCN-dots by\ntuning the excitation wavelength ranging from 950 nm to 980 nm irradiated from\nTi: sapphire Femtosecond laser observed. We have demonstrated the generation of\nhigh energy upconversions with change in energy band gaps as well as number of\nabsorbed photons per photon emitted under the Femtosecond-laser excitation\npower. Additionally, we report the photo luminescence of UCN-dots in visible\nrange with 450 nm excitation wavelength exhibiting blue and red emission\n(visible to visible). The generation of high energy up-conversion in UV-Vis\nregion could be useful for designing optoelectronic and biomedical devices for\ntherapeutic application.\n