  We have studied topological edge states in bowtie ladders with various edge
truncations. The symmetric bowtie ladder, which comprises two trivial
Su-Schrieffer-Heeger (SSH) lattices, exhibits an insulator-metal transition
with trivial insulating states. On the other hand, the lattice can be
transformed into an extended SSH lattice depending on the edge shapes with
non-trivial insulating states in that the winding number is non-zero. The
winding numbers are permutationally designated in the phase diagram depending
on the choice of unit cell. The topological edge states are affected by the
shape of the edge and the corresponding winding number. We also studied general
bowtie ladder models with richer phase diagrams using the characteristics of
the localization length of the edge states showing state bifurcation.
