  The Demazure product gives a natural monoid structure on any Coxeter group.
Such structure occurs naturally in many different areas in Lie Theory. This
paper studies the Demazure product of an extended affine Weyl group $\tilde W$.
The main discovery is a close connection between the Demazure product of an
extended affine Weyl group and the quantum Bruhat graph of the finite Weyl
group. As applications, we obtain explicit formulas on the generic Newton
points and the Demazure products of elements in the lowest two-sided
cell/shrunken Weyl chambers of $\tilde W$, and obtain an explicit formula on
the Lusztig-Vogan map from the coweight lattice to the set of dominant
coweights.
