We address the existence of multipole interface solitons in one-dimensional
thermal nonlinear media with a step in the linear refractive index at the
sample center. It is found that there exist two types of solutions for tripole
and quadrupole interface solitons. The two types of interface solitons have
different profiles, beam widths, mass centers, and stability regions. For a
given propagation constant, only one type of interface soliton is proved to be
stable, while the other type can also survive over a long distance. In
addition, three types of solutions for fifth-order interface solitons are
found.Comment: 5 pages, 5 figure