MIT and Dartmouth College scholars have displayed, in what could be a new innovation, a tool that senses new characteristics of “noise” from the environment that is potent enough to ruin the fragile quantum state of qubits, the fundamental devices of quantum computers.
The advance may help to get insights into microscopic noise processes to reach a hand to engineers to find new ways of protecting qubits.
Qubits are built to screen the two states corresponding to the classic binary bits, a 0 or 1. But, they can also deliver a “quantum superposition” of both states together, allowing quantum computers to fix complex problems that are even impossible for classical computers.
But a qubit’s quantum “coherence” means its strength to retain the superposition state can come apart due to the noise coming from the environment around the qubit. Noise can come from control electronics. It can also arise from the very heart, or impurities in the qubit material itself, and can also have complicated computing errors which will be difficult to remove.
Earlier, many have come up with statistics-based models to gain an approximate on the impact of unnecessary noise sources around qubits to create new plans to protect them and to earn insights into the noise dynamics in itself.
But, those tools were limited. They could barely capture the minimal “Gaussian noise,” which is basically the collection of unrelated disruptions from a large number of sources. It can be best described as white noise arising from the murmuring of a large crowd.
Obviously there’s no particular disruptive trend that stands out, so the qubit isn’t necessarily affected by any one particular source. In such a model, the probability distribution of the noise being created in the shape of the standard symmetrical bell curve. The statistical probability of individual contributors is irrelevant.
The research can be found in the journal, ‘Nature Communications’.