Constructions of symplectic LCD MDS codes from quasi-cyclic codes

Linear complementary dual (LCD) codes play an important role in data storage, communications systems and cryptography. In this paper, we construct some symplectic LCD from quasi-cyclic (QC) codes, prove that these with dimension two over \begin{document}$ \mathbb{F}_{2^a} $\end{document} are maximum-distance-separable (MDS) codes. By extending the generator matrices of MDS two, obtain a series id="M2">\begin{document}$ $\end{document}. As application, new entanglement-assisted quantum error-correcting (EAQECCs) id="M3">\begin{document}$ constructed by