Upconversion of Infrared Light by Graphitic Microparticles Due to Photoinduced Structural Modification

Photoinduced Structural Modification In article number 2300326, Ashim Dhakal and co‐workers show that photo‐induced metastable modification of electronic structure in graphite allows for multiphoton processes that can up‐convert an O‐band infrared excitation to visible‐NIR band in graphite powder. Theoretically, this process can upconvert an infrared light near the wavelength of 3 μm to VIS‐NIR wavelengths. It opens exciting new avenues for applications in visible light generation and low‐noise imaging using infrared light excitation.