Researchers set record by preserving quantum states for more than 5 seconds

(HPCWire) Quantum science holds promise for many technological applications, such as building hackerproof communication networks or quantum computers that could accelerate new drug discovery. These applications require a quantum version of a computer bit, known as a qubit, that stores quantum information.
But researchers are still grappling with how to easily read the information held in these qubits and struggle with the short memory time, or coherence, of qubits, which is usually limited to microseconds or milliseconds.
A team of researchers at the U.S. Department of Energy’s (DOE) Argonne National Laboratory and the University of Chicago have achieved two major breakthroughs to overcome these common challenges for quantum systems. They were able to read out their qubit on demand and then keep the quantum state intact for over five seconds — a new record for this class of devices. Additionally, the researchers’ qubits are made from an easy-to-use material called silicon carbide, which is widely found in lightbulbs, electric vehicles and high-voltage electronics.
“It’s uncommon to have quantum information preserved on these human timescales,” said David Awschalom, senior scientist at Argonne National Laboratory, director of the Q-NEXT quantum research center, Liew Family Professor in Molecular Engineering and Physics at the University of Chicago, and principal investigator of the project. ​“Five seconds is long enough to send a light speed signal to the moon and back. That’s powerful if you’re thinking about transmitting information from a qubit to someone via light. That light will still correctly reflect the qubit state even after it has circled the Earth almost 40 times — paving the way to make a distributed quantum internet.”
By creating a qubit system that can be made in common electronics, the researchers hope to open a new avenue for quantum innovation using a technology that is both scalable and cost-effective.
“This essentially brings silicon carbide to the forefront as a quantum communication platform,” said University of Chicago graduate student Elena Glen, co-first author on the paper. ​“This is exciting because it’s easy to scale up, since we already know how to make useful devices with this material.”
The findings were published on Feb. 2 in the journal Science Advances.