Princeton University is one step closer to silicon-based quantum computing

Researchers developed a device demonstrating the potential to use light as a messenger to connect quantum 'bits' of data

Princeton University has conducted a fresh experiment edging researchers closer to the successful development of a silicon-based quantum computing device.

In collaboration with colleagues at the University of Konstanz in Germany and the Joint Quantum Institute, the Princeton researchers developed a new experimental device that demonstrates the potential to use light as a messenger to connect quantum bits of information, known as qubits, that are not immediately adjacent to each other.

The feat is said to bring the researchers a step closer to making quantum computing devices from silicon, the same material used in today's smartphones and computers.

The team created qubits from single electrons trapped in silicon chambers known as double quantum dots. By applying a magnetic field, they showed they could transfer quantum information, encoded in the electron property known as spin, to a particle of light, or photon, opening the possibility of transmitting the quantum information.

"This is a breakout year for silicon spin qubits," said Jason Petta, professor of physics at Princeton.

"This work expands our efforts in a whole new direction, because it takes you out of living in a two-dimensional landscape, where you can only do nearest-neighbor coupling, and into a world of all-to-all connectivity. That creates flexibility in how we make our devices."

The development of quantum devices could offer computational possibilities that are not possible with today's computers, such as factoring large numbers and simulating chemical reactions. Unlike conventional computers, such devices would operate according to the quantum mechanical laws that govern very small structures such as single atoms and sub-atomic particles.

Major technology firms, such as Intel, are already building quantum computers based on superconducting qubits and other approaches.

"This result provides a path to scaling up to more complex systems following the recipe of the semiconductor industry," added Guido Burkard, professor of physics at the University of Konstanz, who provided guidance on theoretical aspects on the research.

"That is the vision, and this is a very important step."

The breakthrough follows similar news from Intel this week, who announced it has developed inventing a spin qubit fabrication flow on its 300mm process technology using isotopically pure wafers, essentially, quantum processors.