Our friend the electron has been king of the electronics show since vacuum tubes were invented (or maybe longer). The electron’s reign may be coming to a close as more scientists are looking to photons as a replacement for future devices such as smartphones and automobiles. Engineers have been looking to capitalize on optical properties in electronics for some time now and some have actually marketed their new technology in devices we already use, such as Apple’s 2011 MacBook Pro, which features Intel’s Thunderbolt (AKA Light Peak) hardware interface.
Connecting hardware using photons is one thing, but it’s something entirely different when they are used to create an optical switch that could one day be found in micro-circuitry. Scientists from Vanderbilt University, Los Alamos National Laboratory, and the University of Alabama have succeeded in creating a nanoscale optical switch capable of turning on and off trillions of times per second.
Vanderbilt University’s nanoscale optical switch.
(Source: Vanderbilt University)
The switch was made by artificial means using the metamaterial vanadium dioxide (not graphene), a crystalline material that can switch from an opaque-metallic state to a semiconductive state and back again at a rapid pace. The vanadium was deposited on a glass substrate and then coated with a nanomesh of gold nanoparticles, which is not only used for a bling aspect, but as a catalyst of sorts. The scientists blasted the gold mesh with ultra-fast laser pulses, which generated hot electrons that jumped from the mesh to the vanadium, thereby causing it to undergo its phase change in just a few trillionths of a second. Initially, the team fired the laser pulses directly at the vanadium, which worked to cause the transition of the material to its phased state, but found the process went significantly faster and used a tenth of the energy when gold was used.
Here’s the kicker: The new switch is already compatible with current IC technology used in silicon-based chips, meaning that its integration could happen sooner rather than later.