(PhysicsWorld) A team of scientists at Fudan University led by Donglai Feng and Tong Zhang, in collaboration with the group of Zhongxian Zhao and Xiaoli Dong at the Institute of Physics of the Chinese Academy of Sciences, have measured the theoretically predicted value for the conductance of Majorana zero modes (MZM) for the first time. MZM are the potential building blocks of a quantum computer – inside the cores of the vortices formed by a superconductor’s current.
MZMs are zero-energy excitations in a topological superconductor, a material where the surface states differ from the bulk. They are their own antiparticles: if two of them meet, both of them disappear leaving behind only energy. This special property makes them ideal for topological quantum computing.
The main advantage of topological quantum computers is that they are robust against errors. In these devices quantum information is encoded in a pair of spatially well separated Majorana zero modes, and this “nonlocal” storage of information is quite robust – most error mechanisms can only give local perturbations and cannot affect nonlocal storage of information. As a result, while standard quantum computers accumulate errors from random fluctuations over time, topological quantum computers are “topologically protected” meaning only large impacts can cause errors.