Australian, Italian and Swiss scientists have developed a new kind of photonic chip to process quantum information, promising a more robust option for scalable quantum computers.
The study published on Friday in the journal Science Advances demonstrated for the first time that quantum information can be encoded, processed and transferred at a distance with topological circuits on the chip.
The breakthrough could lead to the development of new materials, new generation computers and deeper understandings of fundamental science, according to the study.
The researchers from the Royal Melbourne Institute of Technology, in collaboration with scientists from the Politecnico di Milano and ETH Zurich, used topological photonics to fabricate a chip with a beamsplitter creating a high precision photonic quantum gate.
Topological photonics is a rapidly growing field that aims to study the physics of topological phases of matter in a novel optical context.
“We anticipate that the new chip design will open the way to studying quantum effects in topological materials and to a new area of topologically robust quantum processing in integrated photonics technology,” said Alberto Peruzzo with RMIT.
Peruzzo said that the topological photonics had the advantage of not requiring strong magnetic fields, and featured intrinsically high-coherence, room-temperature operation and easy manipulation.
“These are essential requirements for the scaling-up of quantum computers,” said Peruzzo.
The team was able to use the photonic chip to demonstrate, for the first time, that topological states can undergo high-fidelity quantum interference.
Topologically protected states could add robustness to quantum communication, decreasing noise and defects prevalent in quantum technology, according to the researchers.
Demonstrating high-fidelity quantum interference is a precursor to transmitting accurate data using single photons for quantum communications, a vital component of a global quantum network.