Nano wire gaining popularity

Superconducting devices can be finicky. Often, they’re expensive to manufacture and prone to err from environmental noise. That could change, thanks to research from Karl Berggren’s group in the Department of Electrical Engineering and Computer Science.

The researchers are developing a superconducting nanowire, which could enable more efficient superconducting electronics. The nano wire’s potential benefits derive from its simplicity, says Berggren. “At the end of the day, it’s just a wire.”

Berggren will present a summary of the research at this month’s IEEE Solid-state Circuits Conference.

Most metals lose resistance and become superconducting at extremely low temperatures, usually just a few degrees above absolute zero. They’re used to sense magnetic fields, especially in highly sensitive situations like monitoring brain activity. They also have applications in both quantum and classical computing.

Underlying many of these superconductors is a device invented in the 1960s called the Josephson junction — essentially two superconductors separated by a thin insulator.

“That’s what led to conventional superconducting electronics, and then ultimately to the superconducting quantum computer,” says Berggren.

However, the Josephson junction “is fundamentally quite a delicate object,” Berggren adds. That translates directly into cost and complexity of manufacturing, especially for the thin insulating later.

To overcome these disadvantages, Berggren is developing a new technology — the superconducting nanowire — with roots older than the Josephson junction itself.

Berggren will present a summary of the research at this month’s IEEE Solid-state Circuits Conference.