Lasers can lengthen quantum bit memory by 1,000 times
ANN ARBOR, Mich.—Physicists have found a way to drastically prolong the shelf life of quantum bits, the 0s and 1s of quantum computers.
These precarious bits, formed in this case by arrays of semiconductor quantum dots containing a single extra electron, are easily perturbed by magnetic field fluctuations from the nuclei of the atoms creating the quantum dot. This perturbation causes the bits to essentially forget the piece of information they were tasked with storing.
A quantum dot is a semiconductor nanostructure that is one candidate for creating quantum bits. The scientists, including the University of Michigan’s Duncan Steel, used lasers to elicit a previously undiscovered natural feedback reaction that stabilizes the quantum dot’s magnetic field, lengthening the stable existence of the quantum bit by several orders of magnitude, or more than 1,000 times.