DQCode

The intersection of Quantum Error Correction (QEC) and Distributed Quantum Computing (DQC) promises a pathway to scalable fault-tolerant quantum computing; in particular, qLDPC codes and Type-II architectures both constitute candidates for near-term implementations. In this work, we introduce DQCode for optimised fault-

tolerant logical zero state preparation of the Trivariate Bicycle-[[12, 2, 3]] and Bivariate Bicycle-[[18, 4, 4]] qLDPC codes on distributed Type-II quantum systems.

Based on a QEC cycle-aware qubit mapping, we use a Genetic Algorithm to discover state preparation circuits with optimised telegate counts. Combined with verification circuits for post-selection of runs, this enables efficient fault-tolerant state encoding, which we simulate with open-source Julia software in a realistic DQC setting under circuit-level and Bell pair initialisation noise.

This codebase underlies the MSc thesis "DQCode: Fault-Tolerant Zero State Preparation for Small qLDPC Codes on Near-Term Distributed Quantum Architectures", and provides the optimisation and simulation as well as the plotting scripts utilised in the project.