QDev Seminar: Benjamin James Brown – University of Copenhagen

QDev Seminar: Benjamin James Brown

Niels Bohr International Academy

Cutting corners to achieve Clifford gates with the planar code

Quantum error-correcting codes currently receive significant attention from both the theoretical and experimental communities as their realisation will allow us to maintain coherent quantum states such that they can be used for quantum information processing tasks. In addition to protecting quantum data, it is also important that we can perform unitary rotations on quantum states that are encoded with a quantum error-correcting code. In this talk I will present a new scheme to perform unitary operations with the planar code, which is based on the braiding of non-Abelian point-like defects, or twists, that we find at the corners of the code. Remarkably, the twist defects we study have many properties in common with Ising anyons, and as such, manipulating these point-like objects is also interesting from a fundamental standpoint. Throughout my talk, I will also outline the technical challenges involved in moving corners. In particular, I will show how defect exchange, and in turn the Clifford group, can be achieved with local four-body, and a small number of local five-body parity check measurements.