Scientists at Rutgers University and the University of Florida discovered the “chiral spin mode”, a sea of electrons spinning opposing circles.
“We discovered a new collective spin mode that can be used to transport energy or information with very little energy dissipation, and it can be a platform for building novel electronic devices such as computers and processors,” said Girsh Blumberg, senior author of the study.
Collective chiral spin modes propagate waves of electron spins that do not carry a charge current. But, modify the “spinning” directions of electrons. “Chiral” refers to entities that are matching but asymmetrical and can’t superimpose on their mirror image.
chiral spin modes
Researchers used a custom-made, ultra-sensitive spectrometer to study a prototypical 3D topological insulator. A microscopic theoretical model predicts the energy and temperature evolution of the chiral spin mode.
In a vacuum, electrons are simple, boring elementary particles. But in solids, the collective behavior of many electrons interacting with each other and the underlying platform may result in phenomena that lead to new applications in superconductivity, magnetism and piezoelectricity, to name a few.
Condensed matter science, which focuses on solids, liquids and other concentrated forms of matter. Which seeks to reveal new phenomena in new materials.
Silicon-based electronics, such as computer chips and computers, are one of the most important inventions in human history. But silicon leads to significant energy loss when scaled down. One alternative is to harness the spins of electrons to transport information through extremely thin wires, which in theory would slash energy loss.
The newly discovered “chiral spin mode” stems from the sea of electrons on the surface of 3D topological insulators. These special insulators have non-magnetic, insulating material with robust metallic surfaces, and the electrons confine only on 2D surfaces.
Most importantly, the electrons’ spinning axes are level and perpendicular to their velocity. Chiral spin modes emerge naturally from the surface of such insulating materials, but they never observed before due to crystalline defects.
The experimental observation in the current study made possible following the development of ultra-clean crystals for Emergent Materials.
The discovery paves new paths for building next generation low-loss electronic devices.
More information: [Physical Review Letters]