Almost before 80 years ago, a theoretical physicist Ettore Majorana predicted that there are neutrally charged particles present in nature that acts as its own antiparticle. Now, a team including Standford claims that they have discovered a particle-like system that behaves just like the kind of matter Majorana predicted.
Scientists discovered the material by forcing electrons to flow in opposite directions along the edges of a sandwich of superconducting materials. It could increase the pairs of particles known as ‘Quasiparticles’.
If applying the magnetic field to such particles while they zipped along, it slows down and changes direction in distinct stages. This then exploits to spot a kind of behavior that was a signature of Majorana particles.
Stanford researcher Shoucheng Zhang said, “Our team predicted exactly where to find the Majorana fermion and what to look for as it’s ‘smoking gun’ experimental signature.”
Particles and antiparticles can also go the other way. They are born together in a concentration of energy such as the ones inside particle colliders. A fundamental class of matter called fermion is the best example of it. A fermion is a particle that acts its own antiparticle with the things like electrons, neutrinos, and the quarks making up protons and neutrons.
Photons can be their own antiparticles but they are not fermions. Neutrons would be great candidates since they’re already neutral. But if they brought together with antineutrons, their opposing group of quarks still annihilate each other.
Another interesting candidate is the tiny, near-massless bits of matter, known as neutrinos.
To detect these ghostly particles, researchers are still out on whether they qualify as Majorana fermions, and will be for some time yet. According to them, it could turn out that such particles just don’t exist in the Universe.
Researcher Giorgio Gratta, from Stanford, said, “Where it gets more interesting is that analogies in physics have proved very powerful. And even if they are very different beasts, different processes, maybe we can use one to understand the other. Maybe we will discover something that is interesting for us, too.”
It could reduce the risk of a particle in a quantum computer losing its information. A backup quasi-antiparticle could be just the thing to make the system more robust.
Nobel laureate Frank Wilczek said, “It’s not fundamentally surprising because physicists have thought for a long time that Majorana fermions could arise out of the types of materials used in this experiment.”
“But they put together several elements that had never been put together before, and engineering things so this new kind of quantum particle can be observed in a clean, robust way is a real milestone.”