Laser Embeds Nanoscale Device in Silicon

A team of engineers at Bilkent University, in Ankara, Türkiye, has built a nanoscale optical element not on top of a silicon wafer, but rather in a layer below the surface. To achieve this, they used a special type of laser known as a Bessel beam, whose light can pass through the surface of a wafer and interact with the silicon below. Because the Bessel beam's light doesn't diffract, it's now possible to create two-dimensional structures inside the silicon as small as 100 nanometers.