The main objective in this study is the band structure variance of simple cubic cubic(SC) and face center cubic(FCC) when the refractive index gradually approaches to zero. We discretize Maxwell equation by the Yee's scheme. After singular value decomposition(SVD), we find out its invariant subspace such that we can have the nullspace-free eigenvalue problem with small dimension. We solve this eigenvalue problem by Shift-Invert Residual Arnoldi method(SIRA) and then we are able to draw the band structure. We also have some ideas of the equation as the refractive index is smaller than zero and the experiment results are shown in this thesis. With the chirality parameter growing, the band structures of SC and FCC are compressing.