Efficiently expanding the light spectrum at the smallest scale, across a wide portion of the visible and infrared spectrum

https://www.eurekalert.org/news-releases/1070233

"supercontinuum generation using octave-spanning coherent light at deep-subwavelength scale (<100 nm), employing phase-matching-free 2nd-order nonlinear optical frequency down-conversion in ultrathin gallium selenide/ niobium oxide crystals... difference-frequency generated coherent light with -40 dB spectral width from 565 to 1906 nm, 5 orders magnitude thinner, 2 to 3 orders magnitude less excitation power needed, ringe visibility >0.9 demonstrating superior coherence... metrology, spectroscopy, telecommunications"