(a) The Fourier knot serial in momentum space for the gapless phase of the Kitaev model with respect to different frequency ratios, ω x : ω y . The parameter setting is [ J x = 40 , J y = 10 , J x = 40 ]. (b) The Fourier knot serial with respect to different frequency ratios in the gapped phase of the Kitaev model. The parameter setting is [ J x = 10 , J y = 10 , J x = 40 ].