‘Angel particle’ discovered after 80-year-long hunt
Scientists have discovered the ‘angel particle’ - which is the antiparticle of itself - 80 years after it was predicted to exist, a finding that could one day help make quantum computers more robust.science Updated: Jul 24, 2017 17:55 IST
Scientists have discovered the ‘angel particle’ - which is the antiparticle of itself - 80 years after it was predicted to exist, a finding that could one day help make quantum computers more robust.
In 1928, physicist Paul Dirac predicted that every fundamental particle in the universe has an antiparticle – its identical twin but with opposite charge.
When particle and antiparticle met they would be annihilated, releasing energy.
Few years later the first antimatter particle - electron’s opposite, the positron – was discovered.
However in 1937, physicist Ettore Majorana predicted that in the class of particles known as fermions, which includes the proton, neutron, electron, neutrino and quark, there should be particles that are their own antiparticles.
Scientists from the Stanford University and University of California in the US have found the first firm evidence of such a Majorana fermion.
They have named the Majorana fermion “angel particle,” in reference to Dan Brown’s best-selling thriller “Angels and Demons” in which a secret brotherhood plots to blow up the Vatican with a time bomb whose explosive power comes from matter-antimatter annihilation.
“This discovery concludes one of the most intensive searches in fundamental physics, which spanned exactly 80 years,” said Shoucheng Zhang, professor at Stanford.
Although the search for the famous fermion seems more intellectual than practical, it could have real-life implications for building robust quantum computers, although this is admittedly far in the future, said Zhang, one of the senior authors of the study published in the journal Science.
The particular type of Majorana fermion the research team observed is known as a “chiral” fermion because it moves along a one-dimensional path in just one direction.
Majorana fermions could be used to construct robust quantum computers that are not thrown off by environmental noise, which has been a big obstacle to their development.
Since each Majorana is essentially half a subatomic particle, a single qubit of information could be stored in two widely separated Majorana fermions, decreasing the chance that something could perturb them both at once and make them lose the information they carry.