Two-channel resonance scattering of waves and particles by point and planar defects

The shattering of a wave (quasiparticle) with a dispersion curve consisting of two quadratic branches by a planar defect is discussed. The analog of such a process is the scattering of a similar wave (quasiparticle) in a one-dimensional system by a point defect. It is shown that even when the defect is passive, i.e., has no internal degrees of freedom, scattering may become resonant. The physical explanation of this effect is that a wave with a lower-lying spectrum scattered by the defect is in resonance with a localized (bound) state emerging because of the interaction between the defect and a wave with a higher-lying spectrum. Zh. éksp. Teor. Fiz. 115, 306–317 (January 1999)