Quantum low-density parity-check (QLDPC) codes are the leading candidate for performing error correction in scalable fault-tolerant quantum computing systems. This invention presents a Two-bit Bit Flipping Decoder Diversity (TBF) for quantum low-density parity-check (QLDPC) codes, specifically targeting variable degree-3 QLDPC codes. By using a refined two-bit bit-flipping technique, this decoder improves error correction performance and reduces latency, which are critical for quantum applications. The approach is designed to handle complex configurations, such as trapping sets in hypergraph product codes, which typically lead to iterative decoding failures. This method adds an extra layer of precision by allowing the decoder to handle variable nodes with higher precision, enabling the correction of previously challenging error patterns more effectively than traditional bit-flipping methods. Background: Quantum low-density parity-check (QLDPC) codes have recently gained attention over topological codes due to their superior minimum distance and asymptotically scaling code rates. However, QLDPC codes impose long-range qubit connections that increase noise and add delays, restricting the latency available for decoding. Traditional decoders like belief propagation (BP) and min-sum (MS) struggle with handling trapping sets in QLDPC codes, leading to poor error correction performance, particularly in error-floor regions. The proposed method, adapted from classical error-correction techniques, addresses these issues by allowing greater flexibility in flipping decisions based on node states, making it a low-latency, high-performance solution for quantum applications. This framework allows multiple decoders to operate collectively, which enhances the error-correcting capabilities of QLDPC codes while maintaining computational efficiency. Applications:
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