Designing circuits for a quantum computer

Project leaders: Professors Robert Calderbank and Henry Pfister
Project manager: Narayanan Rengaswamy
Team members: Atsushi Hu, Joey Li, Becca Shapiro

Project summary:
For roughly two decades, theoretical quantum algorithms have been known to provide significant speedup over classical techniques for certain classes of problems. However, building reliable quantum computers in the real world has been challenging due to problems of decoherence in computation. Thus, the field of quantum error correction is extremely important. We describe the results of two experiments conducted on real quantum computers available through the IBM Q Experience that experimentally examine the benefits of quantum error coding. We find that carefully designed fault-tolerant operators for the [[4,2,2]] code decrease the infidelity of computation by a factor of ten, from 2.08 to 0.19. We also confirm that in the [[4,2,2]] code, centralizing operators provide no significant benefits over normalizing operators.

Download the report: "Quantum Benchmarking on the [[4,2,2]] Code"