An artistic view of the subwavelength grating made of layered molybdenum diselenide. The red spheres represent molybdenum atoms, and the blue ones represent selenium atoms. Light is trapped within the grating, which enhances the generation of light at three times the original frequency. Credit: E. Pruszyńska-Karbownik, Faculty of Physics, University of Warsaw Researchers from the Faculty of Physics at the University of Warsaw, working with teams from the Łódź University of Technology, the