Quantum Theory Seminar: Benjamin Brown

Speaker: Benjamin Brown (IBM)

Title: Evading Quantum Noise in Macroscopic Systems

Abstract: A quantum computer will require that we can perform a universal set of logic gates on a large number of protected qubits. What's more these gates must be performed with extremely high fidelity. In this talk I will review some recent experimental progress in the field before discussing theoretical advances in fault-tolerant logic gates. I will talk about how to perform logical operations with the surface code using a connection to Majorana fermions, and I will explain how these measurement based gates are generalised to more general quantum low-density parity-check codes. Lastly, I will mention some unpublished work on how to perform non-Clifford operations by transforming between the surface code into a non-Abelian anyon model to introduce non-trivial phases to encoded logical qubits.