Artificial atoms created for quantum computing

Scientists have created artificial atoms generating unique photons, a breakthrough that could be a big step forward in the development efforts of all-optical quantum computing.

Artificial atoms – which work in the air and at room temperature – were created by drilling holes in a thin two – dimensional sheet of hexagonal boron nitride with a gallium ion beam.

"Our work provides a source of unique photons that can be used as quantum information carriers or qubits. We have structured these sources, creating as much as we want, where we want to, "said Benjamin J Aleman of the University of Oregon in the United States.

"We would like to configure these single photon emitters into circuits or networks on a microchip so that they can communicate with each other, or with other existing qubits, such as spins in the solid state or in the solid state. superconducting circuit qubits, "said Aleman.

Artificial atoms were discovered three years ago in 2D hexagonal boron nitride flakes, a single insulating layer composed of alternating boron and nitrogen atoms in a network also called white graphene.

Researchers use this discovery to produce and use photons as sources of single photons and qubits in quantum photonic circuits.

Traditional approaches to the use of atoms in quantum research have focused on the capture of atoms or ions, and the manipulation of their spin with lasers so that they have a quantum superposition or the ability to combine simultaneously "off" and "on" states.

However, this work required working under vacuum in extremely cold weather with sophisticated equipment.

Motivated by the observation that one frequently finds artificial atoms near an edge, the researchers first created edges in white graphene by drilling circles 500 nanometers wide. and four nanometers deep.

The devices were then annealed under oxygen at 850 degrees Celsius to remove carbon and other residual materials and activate the emitters.

Confocal microscopy revealed tiny spots of light from the drilled regions. Zooming in, the Aleman team found that the individual light spots emit light at the lowest possible level – one photon at a time.

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According to the study published in the journal Nano Letters, individual photons could be used as tiny and ultra-sensitive thermometers, in the distribution of quantum keys or to transfer, store and process quantum information.

"The big breakthrough is that we have discovered a simple, scalable way to nanofabricate artificial atoms on a microchip, and that artificial atoms are working in the air and at room temperature," said Aleman.

"Our artificial atoms will enable many new and powerful technologies. In the future, they could be used for safer and totally private communications and much more powerful computers that could design life-saving drugs and help scientists better understand the universe through quantum computing, "he said. he declared.