In less than 100 seconds, William Wadsworth reveals how he can create bespoke colours of laser light by shining a high-power laser at glass. To explain what is taking place within the glass, Wadsworth uses the analogy of a ball stuck at the bottom of a valley that can be kicked to move it up and down the asymmetric hills on either side. In a similar way, electrons inside the atoms of glass can be given a “kick” with a high-power laser, causing them to oscillate over a range of frequency components – corresponding to different colour emissions.
If lasers are your thing, then don’t forget to also check out the Physics World Focus on Optics & Photonics. This free-to-read issue includes a special feature about the giant laser interferometers underpinning the latest searches for gravitational waves.
