A new study explores the necessity for advances in quantum hardware materials to further develop the capabilities of quantum computers.
The research was conducted by an international team that analysed the current state of research on quantum computing hardware, with the objective of highlighting the difficulties and opportunities facing scientists and engineers.
While conventional computers encode ‘bits’ of information as either 1 or 0, quantum computers create ‘qubits’ of continuous qualities, thus meaning the potential of quantum computers far surpasses the abilities of conventional computers. To reach the ‘quantum advantage’ point, sophisticated control of the underlying materials is necessary.
“There has been an explosion in developing quantum technologies over the last 20 years,” commented Nathalie de Leon, assistant professor of electrical and computer engineering at Princeton University and the lead author of the paper, “culminating in current efforts to show quantum advantage for a variety of tasks, from computing and simulation to networking and sensing.”
In the past, most work has been targeted to demonstrate proof-of-principle quantum devices and processors, de Leon said, but now the field is poised to address real-world challenges.
“Just as classical computing hardware became an enormous field in materials science and engineering in the last century, I think the quantum technologies field is now ripe for a new approach, where materials scientists, chemists, device engineers and other scientists and engineers can productively bring their expertise to bear on the problem.”
The paper is a call to scientists who study materials to turn to the challenge of developing hardware for quantum computing, said Hanhee Paik, corresponding author and a research staff member at IBM Quantum.
“The progress in quantum computing technologies has been accelerating in recent years both in research and industry,” Paik said. “To continue moving forward in the next decade, we will need advances in materials and fabrication technologies for quantum computing hardware — in a similar way to how classical computing progressed in microprocessor scaling. Breakthroughs do not happen overnight, and we hope more people in the materials community will begin to work on quantum computing technology. Our paper was written to give the materials community a comprehensive overview of where we are in materials development in quantum computing with expert opinions from the field.”
Qubits lie at the heart of quantum computers; leading technologies include superconducting qubits, qubits made from trapping ions with light, qubits made from the silicon materials found in today’s computers, qubits captured in “colour centres” in high-purity diamonds, and topologically protected qubits represented in exotic subatomic particles.
The researchers examined the main technological challenges linked with each of these materials and proposed methods for tackling these problems.
In the future, they hope that quantum computers will be able to solve problems that are impossible for today’s computers, such as modelling the behaviours of molecules and providing secure electronic encryption.
“I think (this paper) is the first time that this kind of comprehensive picture has been assembled. We prioritised ‘showing our work,’ and explaining the reasoning behind the received wisdom for each hardware platform,” de Leon explained. “Our hope is that this approach will make it possible for new entrants to the field to find ways to make a big contribution.”