  A five-level M-type scheme in atomic ensembles is proposed to generate a
one-dimensional bipartite superradiance lattice in momentum space. By taking
advantage of this tunable atomic system, we show that various types of
Su-Schrieffer-Heeger (SSH) model, including the standard SSH and extended SSH
model, can be realized. Interestingly, it is shown that through changing the
Rabi frequencies and detunings in our proposed scheme, there is a topological
phase transition from topological trivial regime with winding number being 0 to
topological non-trivial regime with winding number being 2. Furthermore, a
robust flat band with higher winding number (being 2) can be achieved in the
above topological non-trivial regime, where the superradiance spectra can be
utilized as a tool for experimental detection. Our proposal would provide a
promising approach to explore new physics, such as fractional topological
phases, in the flat bands with higher topological number.
