Quantum Robustness...

A study demonstrates that a combination of two materials, aluminum and indium arsenide, forming a device called a Josephson junction could make quantum bits more resilient. Credit: University of Copenhagen image/Antonio Fornieri

Topics: Computer Science, Quantum Computing, Quantum Mechanics

Researchers have been trying for many years to build a quantum computer that industry could scale up, but the building blocks of quantum computing, qubits, still aren't robust enough to handle the noisy environment of what would be a quantum computer.

A theory developed only two years ago proposed a way to make qubits more resilient through combining a semiconductor, indium arsenide, with a superconductor, aluminum, into a planar device. Now, this theory has received experimental support in a device that could also aid the scaling of qubits.

This semiconductor-superconductor combination creates a state of "topological superconductivity," which would protect against even slight changes in a qubit's environment that interfere with its quantum nature, a renowned problem called "decoherence."

The device is potentially scalable because of its flat "planar" surface – a platform that industry already uses in the form of silicon wafers for building classical microprocessors.

The work, published in Nature, was led by the Microsoft Quantum lab at the University of Copenhagen's Niels Bohr Institute, which fabricated and measured the device. The Microsoft Quantum lab at Purdue University grew the semiconductor-superconductor heterostructure using a technique called molecular beam epitaxy, and performed initial characterization measurements.

New robust device may scale up quantum tech, researchers say, Kayla Wiles, Purdue University