UCC research innovations could have an impact on the development of quantum computing

According to University College Cork‘s (UCC) Macroscopic Quantum Matter Group lab researchers, A new superconducting material known as uranium ditelluride (UTe2) has a spatially varying superconducting state. 

This new superconductor can address one of the biggest problems with quantum computing. Lead author and Ph.D. candidate Joe Carroll made the discovery, which was then reported in Nature’s famous magazine. Carroll was collaborating with UCC Professor of Quantum Physics Séamus Davis then. 

Researchers said, “Superconductors are amazing materials with many strange and unusual properties. Most famously, they allow electricity to flow with zero resistance. If you pass a current through them, they don’t start to heat up; they don’t dissipate any energy despite carrying a huge current. They can do this because instead of individual electrons moving through the metal, we have pairs of electrons that bind together. These pairs of electrons together form macroscopic quantum mechanical fluid.”

The scientists discovered that some electron pairs created Electron Pair-Density Waves, which are novel crystal structures made by some electron pairs and embedded in the background fluid. 

They have discovered the first Pair-Density Wave made up of these unusual pairs of electrons, which suggests that these electron pairs contain intrinsic rotational momentum.

He said, “What is particularly exciting for us and the wider community is that UTe2 appears to be a new type of superconductor. Physicists have been searching for material like it for nearly 40 years. The pairs of electrons appear to have intrinsic angular momentum. If this is true, we have detected the first Pair-Density Wave composed of these exotic pairs of electrons.”

This finding has important applications since UTe2 is a unique superconductor with profound potential for quantum computing. Quantum bits, or qubits, are used by quantum computers to store and modify data.

However, the need for each qubit to be in a superposition with two different energies presents a challenge for current quantum computers. Collapsing into the lowest energy level is a simple way to end this quantum state and stop all useful computing.

There has been much research on UTe2 since it was discovered five years ago, and there is evidence that it is a superconductor that might serve as the foundation for topological quantum computing. 

The lifetime of the qubit during computation in such materials is unbounded, bringing up numerous new avenues for more reliable and practical quantum computers. Microsoft has made significant financial investments in topological quantum computing, making it an established theoretical field.

The study group at the Macroscopic Quantum Matter Group Laboratory is happy to have contributed to comprehending UTe2’s basic superconducting features, which may help us develop more useful quantum computers.

The researcher said, “This important discovery will have significant consequences for the future of quantum computing. The University will launch UCC Futures – Future Quantum and Photonics in the coming weeks. Research led by Professor Seamus Davis and the Macroscopic Quantum Matter Group, using one of the world’s most powerful microscopes, will play a crucial role in this exciting initiative.”

Journal Reference:

1. Gu, Q., Carroll, et al. Detection of a pair density wave state in UTe2. Nature. DOI: 10.1038/s41586-023-05919-7