Fig. 5.

Spectra of examples belonging to classes BDI ($\gamma =0$) and D (nontrivial) ($\gamma \ne 0$). Here, the parity of the winding number is odd, and hence the topological edge mode is protected even when $\gamma \ne 0$. Parameters chosen to obtain the figures are: $t=2\hspace{0.17em}{\text{Hz}}^2$, $t\prime =10\hspace{0.17em}{\text{Hz}}^2$, $s=8\hspace{0.17em}{\text{Hz}}^2$, $s\prime =4\hspace{0.17em}{\text{Hz}}^2$, and $\mu =14\hspace{0.17em}{\text{Hz}}^2$.