Study Findings Provide Insights into Topological Quantum Computation

A research group at the International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS) investigated theoretically the charge-neutral Majorana fermions, and proposed a method for their manipulation.

Research associates Dr. Qi-Feng Liang and Dr. Zhi Wang, and PI Dr. Xiao Hu at the International Center for Materials Nanoarchitectonics (WPI-MANA; Director-General: Dr. Masakazu Aono), National Institute for Materials Science (President: Dr. Sukekatsu Ushioda) investigated theoretically the charge-neutral Majorana fermions, and proposed a method for their manipulation. Using a nano quantum device designed based on the topological properties of special superconducting states, Majorana fermions can be transported and exchanged by merely switching local gate voltage.

Majorana fermion was proposed by the Italian theoretical physicist Ettore Majorana in 1937, but their existence has not yet been confirmed as elementary particle. Recently it has been revealed that quasiparticle excitations of special superconducting states behave similarly to Majorana fermions. While Majorana fermions may be stable due to charge neutrality, they are difficult to manipulate using an external field for the same reason.

The MANA research group confirmed that, unlike electrons and photons, braiding of Majorana particles in the designed quantum device obeys non-Abelian statistics, which can be used for quantum computation. This research result contributes to the key technology of topological quantum computation.

The research paper has been published in Europhysics Letters of the European Physical Society as an Editor’s choice. See: http://iopscience.iop.org/0295-5075/99/5/50004/