Physicists at MIT have devised a protocol for verifying the accuracy of quantum experiments.
A recent development offers a method to confirm the validity of experiments investigating the peculiar behavior of atomic-scale systems.
Physics gets strange at the atomic scale. Scientists are utilizing quantum analog simulators – laboratory experiments that involve cooling numerous atoms to low temperatures and examining them using precisely calibrated lasers and magnets – to uncover, harness, and control these unusual quantum effects.
Scientists hope that any new understanding gained from quantum simulators will provide blueprints for designing new exotic materials, smarter and more efficient electronics, and practical quantum computers. But in order to reap the insights from quantum simulators, scientists first have to trust them.
That is, they have to be sure that their quantum device has “high fidelity” and accurately reflects quantum behavior. For instance, if a system of atoms is easily influenced by external noise, researchers could assume a quantum effect where there is none. But there has been no reliable way to characterize the fidelity of quantum analog simulators, until now.
In a study recently published in Naturephysicists from WITH and Caltech report a new quantum phenomenon: They found that there is a certain randomness in the quantum fluctuations of atoms and that this random behavior exhibits a universal, predictable pattern. Behavior that is both random and predictable may sound like a contradiction. But the team confirmed that certain random fluctuations can indeed follow a predictable, statistical pattern.
What’s more, the researchers have used this quantum randomness as a tool to characterize the fidelity of a quantum analog simulator. They showed through theory and experiments that they could determine the DOI: 10.1038/s41586-022-05442-1
The study was funded, in part, by the U.S. National Science Foundation, the Defense Advanced Research Projects Agency, the Army Research Office, and the Department of Energy.