Science News

Mysterious Majoran quasiparticle identified with new system

The mysterious Majoran quasiparticle, also called Majorana fermion, is one of the strangest hypothetical particles ever conceived. It was hypothesized by the Italian physicist Ettore Majorana in 1937 and boasts strange properties including the fact that it is at the same time a particle and its antiparticle so that in certain contexts matter and antimatter can not annihilate themselves and appear as relatively stable couples that can interact even with your environment.

For this reason, in recent years the hypothetical Majorana particle has risen to prominence because it could be used in the context of quantum computing. In a quantum computer based on the Majorana quasiparticles, information would be stored in pairs of particles and the calculations would be determined by the annihilation of the quasi particles with each other depending on how they intertwine. Already in recent years some physicists have declared that they have identified it in some materials. This is the case, for example, of the so-called neutralino, another hypothetical particle of the supersymmetry model that could be a Majorana fermion.

The problem is that it is not possible to manipulate them and create an environment in which to carry out experiments to show their existence with a scientific method.

Now a new study, published this week in Science, proposes a new method for identifying Majorana quasiparticles in materials, as reported by Ali Yazdani, professor of physics at Princeton University and senior author of the study. With this method, according to the physicists who carried out this study, one can “verify their existence by imagining them and we can characterize their expected properties.”

Specifically, physicists have recreated another context in which the Majorana quasiparticle could be identified, that is, in the channel that can be created on the margins of a topological insulator when the latter is put in contact with a superconductor. Since the Majorana particles are formed at the two ends of the wires, it may be possible to visualize them by cutting the wire.

Performing the experiments, the researchers realized that the Majorana quasiparticles appear only when small magnets are magnetized parallel to the direction of electron flow along the channel. The quasi Majorana particle formed with this system is also quite robust according to the researchers, so much so that it resists even the interruption and can be activated and deactivated. The discovery can therefore be an important step forward for the possible use of this particle in the field of quantum computers.