MIT advances quantum information sharing between processors

Researchers at MIT are developing an on-off system that leverages "giant atoms" to enable high-fidelity operations and interconnection between processors.

A key challenge in quantum computing has been to communicate quantum information between distant parts of a processor.

In a paper published in the journal Nature, the MIT researchers constructed “giant artificial atoms” from superconducting quantum bits, or qubits, connected in a tunable configuration to a microwave transmission line, or waveguide.

“Coupling a qubit to a waveguide is usually quite bad for qubit operations, since doing so can significantly reduce the lifetime of the qubit,” says Bharath Kannan, MIT graduate fellow and first author of the paper. “However, the waveguide is necessary in order to release and route quantum information throughout the processor. Here, we’ve shown that it’s possible to preserve the coherence of the qubit even though it’s strongly coupled to a waveguide. We then have the ability to determine when we want to release the information stored in the qubit. We have shown how giant atoms can be used to turn the interaction with the waveguide on and off.”

http://news.mit.edu/2020/giant-atoms-quantum-processing-communication-0729