New Technique Extends the Life of a Qubit

Researchers at the University of Chicago have discovered a way to increase the life of a quantum system by a factor of up to 10,000. The new technique, which extends the state of coherence for qubits in quantum systems, could one day lead to more powerful and reliable quantum computers. The team based their research on solid-state qubits, but they say it could apply to other kinds of quantum systems as well.

According to the press release, the research was based on a fairly simple idea. “With this approach, we don’t try to eliminate noise in the surroundings; instead, we ‘trick’ the system into thinking it doesn’t experience the noise,” said postdoctoral researcher Kevin Miao, the first author of the paper. “In tandem with the usual electromagnetic pulses used to control quantum systems, the team applied an additional continuous alternating magnetic field. By precisely tuning this field, the scientists could rapidly rotate the electron spins and allow the system to ‘tune out” the rest of the noise.”