Density of quasilocalized states along the resonance curves in continuum

Densities of quasilocalized states are calculated and analyzed for a one-di mensional system with a point defect and an FCC crystal with a planar defec t. The density of states displays a pronounced peak that is positioned near the energy (frequency) of resonant transmission of a particle (wave) throu gh the defect but slightly shifted from this energy. The peak nears the res onance frequency and sharpens, tending to a delta function, as the continuu m edge is approached. (C) 2001 MAIK "Nauka/Interperiodica".