A study that could bring quantum computing and information processing a step closer, a group of researchers has said that they have come up with a new method to record and control a single electron behavior at the quantum mechanical level.
The research team, headed by the scientists at the University of Chicago, used laser lights in ultrafast pulses for the experiment.
The laser light controlled the quantum state of electrons. It contained inside nanoscale defects in a diamond. The researchers observed changes in that electron over a time period. They focused on the quantum mechanical property of electrons known as spin.
A quantum-based computer spin states of individual electrons are similar in the way conventional computers hold bits of data, a binary 1 or 0, in a charge state of electron.
A quantum-based computer would represent a quantum bit, known as qubit.
The main center of the research is a quantum spin system, known as a nitrogen-vacancy center, which they explains is an atomic-scale defect found naturally occurring in diamonds.
The researchers, while explaining the nitrogen-vacancy center, said in it there is a single nitrogen atom which sits adjacent to an empty point in the crystalline latticework of the diamond.
Lead author David Awschalom, a molecular engineering professor at a university in Chicago, said, “These defects have attracted great interest of the scientists over the past decade. They provide a test-bed system for developing semiconductor quantum bits as well as nanoscale sensors.”
“Here, we were able to harness light to completely control the quantum state of this defect at extremely high speeds,” he added.
The scientists easily illuminated a single such nitrogen-vacancy center with two laser light pulses, each below a millionth of a millionth of a second.
The time period between the first and second pulse is exceptionally critical. Researchers say this is because the electron will interact with its local surroundings in characteristic way determined by that timescale.
Co-author Lee Bassett, an electrical engineering professor at the University of Pennsylvania, said, “Our goal was to push the limits of quantum control in these remarkable defect systems. But the technique also provides an exciting new measurement tool.”
Evelyn Hu, an electrical engineering and physics professor at the Harvard University, said, “This technique also provides a means of control of the spin state, an important precursor for any quantum information system.”
Researchers term the findings of the study as a milestone in the study of quantum computing.
The research was reported in the online journal Science Express.