While filling your water bottle this morning, you likely weren’t thinking about how water could be at the heart of the next supercomputer. But Dr. Pierre-Nicholas Roy, a University of Waterloo professor, most certainly was. Roy is laying the groundwork for water-based quantum processing by researching the quantum molecular dynamics of water.

Roy’s Canada Research Chair in Quantum Molecular Dynamics has just been renewed and he’s looking forward to digging more deeply into his team’s most recent discoveries. Typically, the team includes around 10 undergraduate and graduate students and post-doctoral researchers. Most of their work is mathematical and computer simulation-based, so rather than stocking a more conventional lab, this Canada Research Chair funding provides for technology and travel to conferences where students collaborate and learn.

“There’s a promise with quantum mechanics that you can build really fast computers and extremely safe encryption,” says Roy. But when he talks about his research, he’s clear that it doesn’t have a direct practical application. “I’m a fundamental theorist, so application is never the goal,” he says. “We don’t build highways. We clear paths in the woods.”

And those woods can be dense: Roy studies how molecules move at the quantum level. He is specifically interested in the water molecule, which his research has shown to have special properties that could be harnessed to store quantum information.

He and his team recently discovered a quantum phase transition in water. “Water can be vapour, liquid or solid—those are its classical phases—but there are other phases that are important for making quantum materials for applications that could be technological,” says Roy.

When water molecules are encapsulated and prevented from forming hydrogen bonds, they behave in interesting ways. “We have found that water molecules align if they are close together, and become disordered when far apart,” Roy says. “When confined, the water molecules can align or not, and it gives them very special electric properties at the nanometre scale.”

But taking advantage of quantum properties like this can be tricky. Quantum information can be stored when molecules are in a state of coherent superposition, like when water molecules are aligned and entangled, but eventually they return to a state of decoherence and can no longer retain the quantum information. So, the goal is to find strategies to protect coherence for as long as possible.

“There are different ways to protect coherence, and one candidate in the water molecule is the nuclear spin of the proton,” says Roy. The spin is special because it takes longer for molecules to change their nuclear spin state. “Whereas transitions due to rotations and vibrations usually take picoseconds to occur, spin conversion can take hours. So by using nuclear spin and nano-confinement, you can potentially keep quantum information for much longer.”

Nuclear spin conversion is a key area of the research that Roy plans to continue with the support of his renewed Canada Research Chair funding. He and his team are clearing a path in the woods that may eventually lead to a water-based quantum processing highway.

This article was adapted and published with permission from the University of Waterloo.