80 years after it was first theorized by an Italian physicist, evidence of what appears to be Majorana Fermions was discovered by scientists from Stanford University in California and University of California.
According to a theory, when the Big Bang happened 13.7 billion years ago it was believed to have created matter and antimatter in equal quantities. Thus, for every electron, there is a positron, and for every quark, there would have been an antiquark.
The theory further suggests that the laws of nature required matter and antimatter be created in pairs. It was said that the two were mirror images of each other, but with opposite electric charge and other quantum numbers despite having the same mass.
For some unexplained reasons, within a milli-fraction of a second after the Big Bang, matter outnumbered its opposing particle by a hair.
Apparently, for every billion antiparticles, there were a billion and one particles. This phenomenon resulted in the annihilation of antimatter within a second of the creation of the universe, leaving behind only matter.
Up to this day, scientists are still trying to uncover the reason behind this ‘asymmetry’ that resulted only in the survival of matter.
Majorana Fermion: The Future of Quantum Computing
In 1937, theoretical physicist Ettore Majorana theorized the existence of another class of particle known as fermions. Fermions are not matter nor antimatter. Instead, they are both.
On Friday, an article published in the prestigious journal Science reported that researchers found evidence of the existence of Majorana fermions.
The team of scientists labeled the quasiparticle as ‘Angel Particle,’ after the infamous bomb made of matter and antimatter in the Dan Brown thriller Angels and Demons.
For the experiment, Professor Shoucheng Zhang and his team from Stanford University used a thin film of a topological insulator, which conducts electricity on its edges but is insulating within, and coupled it with a layer of superconductor where electrons can flow without resistance. Then, a magnet was swept over the stack. The layer of materials showed varying electrical conductivity in “discrete jumps of the size expected for Majorana fermions.”
“The experiment came out exactly in the way we predicted,” Zang said.
To set the records straight, what the researchers discovered were just quasiparticles and not the actual Majorana fermions. According to a statement from Giorgio Gratta, a Stanford physics professor:
“The quasiparticles they observed are essentially excitations in a material that behave like Majorana particles. But they are not elementary particles and they are made in a very artificial way in a very specially prepared material. It’s very unlikely that they occur out in the universe, although who are we to say? On the other hand, neutrinos are everywhere, and if they are found to be Majorana particles we would show that nature not only has made this kind of particles possible but, in fact, has literally filled the universe with them.”
Quasiparticles are not particles. They are used by scientists as a stand-in for particles that might not actually be there but whose surroundings are registering effects that make it seem as though they are there.
In the past, several experiments also showed traces of Majorana fermions. However, what Zang and his team accomplished gave scientists a glimpse of a different side of the quasiparticle. Taylor Hughes, another theoretical physicist from the University of Illinois, said:
“Certainly as far as chiral Majorana fermions go, this is the only definitive evidence that has been reported.”
The possible existence of fermions could lead to a technological revolution that will see quantum computers as a reality in the near future.
Apparently, a quantum bit or qubit of information can be stored in two separate ‘Angel Particles’ or Majorana fermions. Meaning, if one information got affected by interference, the other particle holding the same information will keep it safe.
A qubit can hold multiple bits of information. Now, imagine storing a qubit in a fermion.
Scientists believe that the discovery of Majorana fermions is a breakthrough that could boost the development of present day quantum computers like the D-Wave of Google and NASA.