  A principal possibility of formation the nanostructures on the surfaces of
50PbO-25Bi$_2$O$_3$-20Ga$_2$O$_3$-5BaO (doped by Eu3+, Er3+, Dy3+) is
demonstrated by using multi-coherent beams. As a sources of the photoinducing
coherent light we have used nanosecond Nd:YAG and Er:Yb lasers generating at
1064 nm and 1540 nm, respectively. The morphology of the photoinduced surfaces
is sensitive to the type of rare earth ions. The thickness of the layer was
about 20-30 nm. Possible mechanisms are explained by coherent photoinduction of
the valence electrons.

Materials Science;Optics