Decoding Quantum Low Density Parity Check Codes

Joschka Roffe (The University of Edinburgh) https://simons.berkeley.edu/talks/jos... Advances in Quantum Coding Theory This talk is a survey of decoders for quantum low density parity check (LDPC) codes, focusing on variants of the belief propagation (BP) algorithm. I will explain why the straightforward implementation of BP fails in the quantum setting and outline how post-processing with ordered statistics can be used to recover good performance. The trade-off between speed and accuracy will be explored, as well as strategies for adapting BP-based decoders to circuit-level noise models. Finally, I will present examples of how open-source software can be used to benchmark the decoding of quantum LDPC codes.