Demonstrating non-Abelian braiding of surface code defects in a five qubit experiment

TL;DR

This paper demonstrates non-Abelian braiding of surface code defects, simulating Majorana exchange operations on a five-qubit IBM processor, providing experimental evidence of their non-trivial quantum behavior.

Contribution

It presents the first experimental demonstration of non-Abelian braiding of surface code defects using only five qubits on a real quantum processor.

Findings

Successful implementation of Majorana exchange on five qubits

Observation of non-trivial effects consistent with theoretical predictions

Accessible presentation for both professional and amateur scientists

Abstract

Currently, the mainstream approach to quantum computing is through surface codes. One way to store and manipulate quantum information with these to create defects in the codes which can be moved and used as if they were particles. Specifically, they simulate the behaviour of exotic particles known as Majoranas, which are a kind of non-Abelian anyon. By exchanging these particles, important gates for quantum computation can be implemented. Here we investigate the simplest possible exchange operation for two surface code Majoranas. This is found to act non-trivially on only five qubits. The system is then truncated to these five qubits, so that the exchange process can be run on the IBM 5Q processor. The results demonstrate the expected effect of the exchange. This paper has been written in a style that should hopefully be accessible to both professional and amateur scientists.