New research published by the University of California, Berkeley, shows that graphene — an incredibly thin and flexible form of carbon — can be used to boost the transmission and switching speed of optical modulators, the building blocks of routers that form the backbone of the internet.

Scientists at UC Berkeley, led by professor Xiang Zhang, have found that one-atom-thick layers of graphene can switch light on and off incredibly quickly. With just the right amount of positive voltage, graphene turns opaque, stopping any light from passing through — and with a negative voltage, graphene can be turned transparent again. The team then successfully shrunk a graphene optical modulator down to 25 square microns in size — small enough to include in silicon circuitry — and modulated it at a speed of 1GHz. The researchers say that modulation speeds of up to 500GHz are theoretically possible, though — and for comparison, the modulators found in 40Gbit switches are measured in centimeters and operate at just 40GHz.

It doesn’t end with faster switching speeds, though. Graphene, unlike current modulators, can absorb — and thus modulate — an incredibly broad spectrum of light, from ultraviolet through to infrared. In other words, with every on/off pulse, a graphene modulator can transmit a huge amount of data using spectral bandwidth that conventional modulators can only dream of. Professor Xiang Zhang, in an attempt to boil his group’s new findings into consumer-speak, puts it this way: “Instead of broadband, we will have ‘extremeband.'” — if graphene modulators can actually operate at 500GHz, we could soon see networks that are capable of petabit or exabit transmission speeds, rather than megabits and gigabits.

Graphene, if you haven’t heard of it before, is a crystallized form of carbon that is something of a “wonder material.” It’s incredibly cheap to make, and it also happens to be the thinnest and strongest crystalline material in the known universe. It can be easily extracted from graphite, the substance used in pencil lead, and, to top it all off, graphene is a good conductor of heat and electricity. All of these factors combine to make graphene not only an excellent optical modulator, but also a prime candidate for future advances in silicon chip lithography.

These graphene optical modulators are the real deal — they’re not some flash in the pan research project that will fizzle into the digital ether. We could see graphene-powered core routers within a few years, and after that, it won’t be long until graphene modulated communications find a place in just about every kind of digital interconnect.

Read more at UC Berkely News Center