Function at the junction

Unless the laws of physics are repealed, chipmakers will soon run smack dab into some fundamental barriers. Tapping into an advanced superconductor technique, Mark Bocko and two research colleagues believe they've discovered a path around those physical barriers that will create a device with a clock speed more than 50 times faster than Intel's vaunted 1-GHz Pentium.

Bocko, a professor of electrical and computer engineering at the University of Rochester in New York, uses a technique called Josephson junctions to make a superconducting chip. The junction is a weak link between two superconducting films separated by a thin oxide layer. Current passing between two superconductors separated by a small junction creates a tunneling effect. The university team says the junctions act like conventional transistors. The key difference is that the on-off operation happens at two-trillionths of a second—a speed that leaves traditional transistors in the dust.

To complete its prototype, the research team designed a tool that directly measures the time intervals between ticks of a superconducting clock made of extremely fast Josephson junctions. Bocko says a chip based on the junctions generates very little heat, thus making it ideal for ultrafast cube-shaped devices. "Superconductors are a realistic alternative to semiconductors for future electronics," he asserts. "And that's without a billion-dollar fabrication facility to make it."