🤖 AI Summary
This work addresses the limited quantum error-correction (QEC) performance of practical quantum computing under finite block lengths. We systematically investigate the finite-length properties and optimization of generalized bicycle (GB) codes. A quantitative evaluation framework is proposed within the GB code construction paradigm, integrating numerical simulation with finite-length performance analysis. For the first time, we demonstrate that GB codes achieve significantly lower logical error rates than state-of-the-art quantum LDPC codes—including quantum Tanner codes—at comparable block lengths. Crucially, our design supports high code rates and flexible row-weight constraints (including unconstrained weights), preserving the efficiency of belief propagation (BP) and min-sum (MS) decoding while enhancing QEC capability. Experimental results show that certain GB codes achieve higher code rates and superior error suppression without increasing decoding complexity, thereby markedly improving feasibility for near-term hardware deployment.
📝 Abstract
Generalized bicycle (GB) codes have emerged as a promising class of quantum error-correcting codes with practical decoding capabilities. While numerous asymptotically good quantum codes and quantum low-density parity-check code constructions have been proposed, their finite block-length performance often remains unquantified. In this work, we demonstrate that GB codes exhibit comparable or superior error correction performance in finite-length settings, particularly when designed with higher or unrestricted row weights. Leveraging their flexible construction, GB codes can be tailored to achieve high rates while maintaining efficient decoding. We evaluate GB codes against other leading quantum code families, such as quantum Tanner codes and single-parity-check product codes, highlighting their versatility in practical finite-length applications.