Mathematical Research Letters
Volume 2 (1995)
Perturbation formulae for the Schrödinger operator with a periodic potential near planes of diffraction
Pages: 59 – 74
Perturbation formulae for Bloch eigenvalues and their spectral projections in a vicinity of the von Laue diffraction planes are constructed. They are converging series with respect to a model operator, roughly taking into account the diffraction inside the crystal. The behaviour of the isoenergetic surface near the von Laue diffraction planes is described.