Researchers generate new silicon structure for quantum computing development

Quantum leap claimed in development of quantum computing

Researchers at Princeton University have made what they say is a significant leap towards making quantum computing technology with standard silicon-based materials.

They've created a piece of silicon-based hardware that can control quantum behaviour between several electrons and with relatively high precision.

The scientists believe that their research, published in the journal Science, represents a groundbreaking process towards quantum computing.

The research details a process including a gate that carefully manages interactions between electrons so that they act as 'quantum bits' of information.

According to the scientists, the demonstration of this technology was almost error free. Jason Petta, a professor of physics at Princeton University, said that a two-qubit gate was the minimum needed to demonstrate that it could work.

"We knew we needed to get this experiment to work if silicon-based technology was going to have a future in terms of scaling up and building a quantum computer," he said.

"The creation of this high-fidelity two-qubit gate opens the door to larger scale experiments."

One of the advantages of basing quantum computers on silicon is cost, given that silicon is well-established in standard computing. It should therefore be cheaper and easier to manufacture when it comes to creating a quantum computer than more esoteric or novel materials.

Research groups and companies have demonstrated devices containing 50 or more qubits, but they require costly materials, such as superconductors or charged atoms.

Interest in quantum computing has grown significantly in recent years. It should be capable of solving problems inaccessible with normal computers.

The Princeton researchers' process involves a two-qubit silicon-based gate, which is made up of two electrons (blue balls with arrows) that are stored in a layer of silicon (Si).

Researchers then applied voltages through aluminum oxide (Al2O3) wires (red and green). As a result, they were able to trap the electrons and generate quantum behaviours.

"The challenge is that it's very difficult to build artificial structures small enough to trap and control single electrons without destroying their long storage times," said David Zajac, a graduate student who worked on the study.

"This is the first demonstration of entanglement between two electron spins in silicon, a material known for providing one of the cleanest environments for electron spin states."