‘Angel particle’ mimics may be first step to reliable quantum computers
- A team of researchers led by physicists from the Chinese Academy of Sciences reports subatomic breakthrough
- The scientists say groups of particles can behave like the theoretical particle which also has its own antiparticle
What is quantum computing and how does it work?
The subatomic particles at the heart of the technology are fragile, short-lived and prone to error if exposed to even a slight disturbance from the surroundings. That means scientists usually have to run quantum computers in extremely cold and isolated environments.
But an exception is the elusive “angel particle”, proposed by the Italian theoretical physicist Ettore Majorana in 1937, and closely linked to the formation of dark matter. Its properties could overcome quantum computing’s sensitivity to the environment.
When the scientists produced a large number of magnetic whirling “storms” over the surface of a superconducting material, they found some of the particles in each vortex formed groups – called Majorana Zero Mode (MZM) – that resembled the angel particle.
In a paper published in the journal Nature on Wednesday, the team said more than 90 per cent of the vortices were topological and possessed the characteristics of isolated MZMs at the vortex centre, forming a grid-like lattice structure that could be controlled by an external magnetic force.
This quality could make them building blocks for topological quantum bits – the basic memory units of quantum computing – but with more resistance to environmental noise than standard qubits, and potentially capable of creating more stable and fault-tolerant computers.
Most particles have antiparticles, with the same mass but carrying the opposite electric charge. When they meet, they annihilate each other, which converts their mass into energy.
But the angel particle proposed by Majorana is an exception, because it is also its own antiparticle, a property that makes it a strong candidate for dark matter, according to some physicists.
In the study, the researchers created rows of MZMs. Their simultaneous particles and antiparticles operated like the angel particle, which has yet to be discovered, making it possible to store information in both halves of a split electron.
For a topological qubit to be disturbed, the information stored in each half of a split electron would have to be interfered with at the same time.
Chinese scientists may be a step closer to a quantum code-breaking machine
While classical computing uses the “bit” – representing zero or one – as its basic unit of information, the qubit has the flexibility to represent zero, one or both at the same time – one of the simplest expressions of the peculiarity of quantum mechanics.
Because quantum computers’ basic information units can represent all possibilities simultaneously, they are theoretically much faster and more powerful than the regular computers we are used to.
The team includes scientists from the Beijing National Centre for Condensed Matter Physics and Institute of Physics at the CAS as well as Japan’s RIKEN research institution for theoretical and mathematical sciences, and Boston College in the US.
New study reveals time can flow either way in quantum physics
“We have demonstrated that the ordered lattice is tunable by external magnetic fields and observed the coupling between the MZMs under high magnetic fields,” they wrote.
Their next step is to figure out how to braid the rows of MZMs to form the topological qubits needed to build a usable computer.
“Our findings provide a pathway towards tunable and ordered MZM lattices as a platform for future topological quantum computation,” they wrote.
