New research published in the October 3rd issue of the journal Science suggests that a team of Princeton researchers may have finally identified a so-called Marjorana particle. This until now only theoretical particle is capable of existing as both matter and antimatter at the same time. The fabled subatomic particle is named after Italian physicist Ettore Majorana who first suggested that some particles might be their own antimatter partners back in 1937.
Antimatter Marjorana particle observed in special superconductor
The Majorana particle was seen inside a specially designed superconductor, a substance where electrons can move freely and that permits electricity to flow without resistance. The research team was led by Prof. Ali Yazdani of Princeton University.
The project involved setting a long chain of magnetic iron atoms on top of a superconductor made of lead. Magnetism disrupts superconductors, which depend on a lack of magnetic fields in order for electrons to flow freely. For this special superconductor, however, the magnetic chain created a type of superconductor in which adjacent electrons in the chain coordinated their spins to satisfy the requirements of both magnetism and superconductivity. The researchers say that each of these pairs is in effect an electron and an antielectron, each with a negative and a positive charge. This particular subatomic structural arrangement means one electron at each end of the chain dies not have a neighbor to pair with, which causes these electrons to take on the properties of both electrons and antielectrons—in other words, Majorana particles.
Antimatter Marjorana particle: Strongly confirmatory, but not definitive evidence
This new research definitely seems to confirm the existence of Majorana particles, explains Leo Kouwenhoven of the Delft University of Technology in the Netherlands (did not participate in the research) who has found evidence of Majorana particles in a different superconductor arrangement. “But to really speak of full proof, unambiguous evidence, I think you have to do a DNA test.” This kind of a test would need to show the particles do not obey the usual laws of the two known classes of particles in nature—fermions (protons, electrons and most other particles) and bosons (photons and other force-carrying particles, including the Higgs boson). “The great thing about Majoranas is that they are potentially a new class of particle,” Kouwenhoven continues. “If you find a new class of particles, that really would add a new chapter to physics.”
Physics faculty member Jason Alicea of California Institute of Technology (did not participate in the research) said the new research provides “compelling evidence” for Majorana particles, but that “we should keep in mind possible alternative explanations—even if there are no immediately obvious candidates.”