Photon upconversion involves a series of non-linear optical processes where the sequential absorption of two or more photons leads to the emission of a single photon with energy greater than the sum ...

The James Webb Space Telescope has transformed how scientists study the universe. With its unmatched ability to detect near-infrared light, it reveals details of distant galaxies once thought ...

Two-photon technology, which relies on overlapping ... and it must have widely separated absorption, emission and fluorescence spectra. Materials that meet these criteria now exist and can be ...

Hot gases don’t produce a continuous emission spectrum. Black hydrogen absorption lines are at the same wavelength as the bright hydrogen emission lines. Key fact Line emission spectra are ...

This work reports the design of an efficient multiband UC system based on Ln3+/Yb3+-doped core-shell upconversion ...

A hybrid electroluminescence device achieves room-temperature single-photon emission, advancing quantum technologies with ...

This means that each electron transition will produce a photon of a different frequency and hence a different colour. This causes line emission spectra to be produced, as shown below. This is not ...