Proposed by the mathematician and physicist Hermann Weyl in 1929, Weyl fermions have been long sought by scientists because they have been regarded as possible building blocks of other subatomic particles, and are even more basic than the ubiquitous, negative-charge carrying electron (when electrons are moving inside a crystal). Their basic nature means that Weyl fermions could provide a much more stable and efficient transport of particles than electrons, which are the principle particle behind modern electronics. Unlike electrons, Weyl fermions are massless and possess a high degree of mobility; the particle's spin is both in the same direction as its motion — which is known as being right-handed — and in the opposite direction in which it moves, or left-handed.
"The physics of the Weyl fermion are so strange, there could be many things that arise from this particle that we're just not capable of imagining now," said corresponding author M. Zahid Hasan, a Princeton professor of physics who led the research team.
The researchers' find differs from the other particle discoveries in that the Weyl fermion can be reproduced and potentially applied, Hasan said. Typically, particles such as the famous Higgs boson are detected in the fleeting aftermath of particle collisions, he said. The Weyl fermion, however, was discovered inside a synthetic metallic crystal called tantalum arsenide that the Princeton researchers designed in collaboration with researchers at the Collaborative Innovation Center of Quantum Matter in Beijing and at National Taiwan University.
The Weyl fermion possesses two characteristics that could make its discovery a boon for future electronics, including the development of the highly prized field of efficient quantum computing, Hasan explained.
For a physicist, the Weyl fermions are most notable for behaving like a composite of monopole- and antimonopole-like particles when inside a crystal, Hasan said. This means that Weyl particles that have opposite magnetic-like charges can nonetheless move independently of one another with a high degree of mobility.
For the full story: http://www.princeton.edu/research/news/features/a/?id=15286