Researchers from Rutgers, IBM and collaborating institutions have shown that a quantum computer can check what is happening inside it and respond while it is running, repeatedly resetting parts of the system to bring chaotic behavior under control.

The advance is a critical step toward building larger, more reliable quantum computers. 

Today’s quantum computers operate according to the unusual rules governing atoms and other extremely small particles. They could one day solve problems beyond the reach of conventional computers — designing better batteries and cleaner industrial catalysts, simulating molecules and materials too complex for today’s computers, and running certain artificial intelligence programs.

In a study published in Nature Physics, researchers from Rutgers, International Business Machines Corp., and collaborating institutions showed that a quantum computer can repeatedly check and reset parts of itself while running. The experiment is among the largest demonstrations to date of real-time quantum feedback control, a capability considered essential for future quantum computers that will be fault tolerant.