Moving beyond silicon to break the MegaHertz barrier

We're rapidly closing in on a decade since the first desktop processors cleared the 3GHz mark, but in a stunning break from earlier progress, the clock speed of the top processors has stayed roughly in the same neighborhood since. Meanwhile, the feature shrinks that have at least added additional processing cores to the hardware are edging up to the limits of photolithography technology. With that as a backdrop, today's issue of Science contains a series of perspectives that consider the question of whether it's time to move beyond semiconductors and, if so, what we might move to.