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With some derivations, we can show that the winding number in the SSH model is exactly the Berry phase of the system. The winding number can be defined in a more general form. The integral of the Berry curvature of the energy eigenstate on the surface of k-space is called "Chern number", which is defined as following  \begin{equation}  Q^(n)=-\frac{1}{2\pi}\oint_{S}\textbf{b}_ndS Q^n=-\frac{1}{2\pi}\oint_{S}\textbf{b}_ndS  \end{equation}