A university spinoff company is seeking to commercialise superconducting wires. 

Superconductivity, where electrical resistance vanishes, remains a technology that both powers science and mystifies scientists. 

It charges MRI scanners, enables new drug discovery through advanced spectroscopy machines, and is used to create the kind of powerful magnets that help smash atoms in high-tech labs.  

In all of its uses, the next-generation machines have one common connection - superconducting wires. 

The only person who can make these wires is Dr Venkat Selvamanickam from the University of Houston (UH). 

His high-temperature superconducting wires can carry up to 600 times the current carrying capacity of regular copper wires of the same size. 

He has launched a company called AMPeers, short for Advanced Materials Pioneers, in partnership with UH, and has received three grants totaling $1.6 million (two from the Department of Energy and one from the US Navy) to accelerate utilisation of the technology.  

“AMPeers is scaling up UH-developed superconductor technologies to manufacturing and commercialisation and these awards will help reach our goals faster,” Dr Selvamanickam says.

The superconductor wires, called Symmetric Tape Round, or STAR, are the only superconductor wires available with a diameter of just 1–2 mm, bend radius capability of 15 mm, and high current-carrying capacity over a wide range of temperatures from 4.2 Kelvin to 77 Kelvin. 

Other round superconductor wires cannot be bent to such small diameters or cannot be used at temperatures much higher than 4.2 Kelvin. A broader operating temperature range makes many more uses feasible. 

The enabling technology of STAR wires is a unique superconductor symmetric tape technology developed by AMPeers and UH. 

The tape is called RE-Ba-Cu-O (REBCO, RE= rare earth) superconductor film. Symmetric REBCO tapes can be bent to 0.8 mm in diameter while retaining greater than 95 per cent of their current-carrying capacity, whereas standard REBCO tapes degrade even below 6 mm bend diameter. 

This superior bendability enables powerful, yet compact magnets. 

“In our phase-one work, we reduced the cost of the wire. Now, in phase two, with $1.15 million from the DOE, we will work to scale up our manufacturing of the low-cost wire and also make the wires longer. The second grant, $200,000 also from the DOE, will be used to develop multi-strand cables with these wires,” said Dr Selvamanickam.   

For the Navy, which uses the REBCO wires to enable high power density that addresses the needs of their advanced power systems, Dr Selvamanickam and company will work out the kinks, or hot spots that can occur when such high current densities are sustained. 

Elimination of such hot spots is important to avoid catastrophic failure of the superconducting device.   

“While long tapes with uniform current-carrying capability are highly desirable to avoid such hot spots, methods to manage local defects in REBCO tapes have to be developed since that is lot more practical,” he said. 

The three grants from the DOE’s High Energy Physics office and the Navy brings to six the number AMPeers has received from them in five years since its founding.