Quantum Quasi-Cyclic LDPC Codes

In this paper, a construction of a pair of "regular" quasi-cyclic LDPC codes as ingredient codes for a quantum error-correcting code is proposed. That is, we find quantum regular LDPC codes with various weight distributions. Furthermore our proposed codes have lots of variations for length, code rate. These codes are obtained by a descrete mathematical characterization for model matrices of quasi-cyclic LDPC codes. Our proposed codes achieve a bounded distance decoding (BDD) bound, or known as VG bound, and achieve a lower bound of the code length.