Credit: University of Rochester illustration / Michael Osadciw

Researchers say they have proof-of-concept of an approach that could dramatically speed up computer processing. As seems to be the case with 90 percent of technological advances these days, it involves graphene.

The University of Rochester researchers were trying to find a faster way to use logic gates, the physical component in a processor that outputs the 0s and 1s used to represent data. They are limited by how quickly you can generate individual bursts of electricity.

In principle, using lasers rather than transistors would do this much faster, but in practice it’s been too difficult to process the information quickly enough to take advantage of this idea.

The researchers used the approach of “illuminating tiny graphene-based wires connecting two gold metals.” Their breakthrough was to distinguish between electrons acting as “real” and “virtual” charge carriers. The former continued moving after the laser pulse was switched off, while the latter only move with the laser switched on.

Measuring that meant two laser pulses, each with two possibilities (real or virtual), could combine to form the logic gate. Compared with current computers, it reduced the timescale for processing from nanoseconds (billionths of seconds) to femtoseconds (millionths of a billionth of seconds).

However, project leader Tobias Boolakee was realistic about the implications: “It will probably be a very long time before this technique can be used in a computer chip, but at least we now know that lightwave electronics is practically possible.”