Nanosilicon provides pumping levels and the localized states produced from Si–Yb bond on bulge surface of silicon film generate stimulated emission, in which a four-level system is built for chip-laser. The Si–Yb nanobulges on Si film cause a remarkable increase of the surface area and make a buffering layer for mismatch between Si and Yb lattices. Dynamics of photoluminescence and electroluminescence on nanosilicon coated by Yb is investigated. Stimulated peaks near 700 nm are observed on silicon quantum dots coated by Yb. Enhanced EL peaks in the wavelength region from 1300 nm to 1650 nm are measured on the Si film coated by Yb. Si–Yb quantum cascade laser is designed, in which emission wavelength could be manipulated into the window of optical communication by Si–Yb bonding on bulge surface of Si film.