Superconducting Niobium Chip Smashes Silicon Power Consumption Standards

When it comes to energy efficiency, today’s computers eat up some eight orders of magnitude more than the theoretical minimum. Clearly, there’s room for improvement.

Today, Quentin Herr and pals at Northrop Grumman Systems in Baltimore reveal a superconducting logic device that uses 300 times less power than conventional silicon chips. That’ll be a shock to chip-makers whose attempts at energy efficiency improvements pale in comparison.

The laws of physics help, of course. The power dissipated by a conventional transistor depends on its size and on the material from which it is made.

By comparison, the energy dissipated by the superconducting equivalent, the Josephson junction, is determined only by thermal noise, the system being entirely free of the troublesome resistance that eats up energy in conventional devices.

To exploit this, Herr and co developed and built a new type of device known as a reciprocal quantum logic chip. Their superconducting chip is made of niobium, operates at 4.2 kelvin and consists of 1600 Josephson junctions .

They say it can operate at clock speeds of 6 Ghz with a 6 mW power supply, that faster speeds are possible and that this performance can scale to chips with a million junctions. And it does it with a bit error rate of less than 10^-40. That’s practically nothing.

But the jaw dropper is the power consumption which is only three orders of magnitude above the theoretical limit.