Scientists may have uncovered a new behavior in materials that could be huge when it comes to quantum computers. The new findings provide evidence for a long-sought phenomenon in a two-dimensional magnet.
A theoretical model was already developed to explain microscopic magnets. These magnets interact in a way that leads to a disordered state known as a quantum spin liquid. This "Kitaev quantum spin liquid" supports magnetic excitations equivalent to Majorana fermions. These are particles that actually have their own antiparticles.
Majorana fermions are interesting to scientists because they have the potential to be used as qubits in quantum computers. Qubits are effectively the computer's version of "bits" that have the dual state of functioning as both 1s and 0s at the same time.
In this latest study, the researchers wanted to see if Kitaev interactions existed in nature in certain materials containing magnetic ions that exhibit a strong coupling. One way to watch spin liquid physics in such a material is to "splash" or excite the liquid using neuron scattering.
The researchers used this "splash" technique to look at a two-dimensional graphene-like material called alpha-ruthenium trichloride. They found that the form of magnetic excitations created in the material was different from spin waves seen in ordinary magnets. However, it matched the spectrum predicted for Majorana fermions.
"The observation of these fractionalized excitations is truly remarkable," said Steve Nagler, co-corresponding author of the new paper detailing the study. "There has been a huge push recently to see if Kitaev quantum spin liquid physics can be found in materials. Time will tell whether this represents a first step on the road to a new qubit technology."
The findings could be huge when it comes to designing quantum computers. If scientists have this type of qubit technology, this will represent the basis of quantum computers and how they store information.
"This study proved that the proper honeycomb lattice materials can have the exotic excitations long sought by the scientific community, potentially bringing us closer to realizing Kitaev's vision of topologically protected quantum information," said Alan Tennant, co-author of the new paper detailing the study.
The findings are published in the April 4 issue of the journal Nature Materials.
