On absence of embedded eigenvalues for Schrödinger operators with perturbed periodic potentials

Abstract

The problem of absence of eigenvalues imbedded into the continuous spectrum is considered for a Schrödinger operator with a periodic potential perturbed by a sufficiently fast decaying ``impurity'' potential. Results of this type have previously been known for the one-dimensional case only. Absence of embedded eigenvalues is shown in dimensions two and three if the corresponding Fermi surface is irreducible modulo natural symmetries. It is conjectured that all periodic potentials satisfy this condition. Separable periodic potentials satisfy it, and hence in dimensions two and three Schrödinger operator with a separable periodic potential perturbed by a sufficiently fast decaying ``impurity'' potential has no embedded eigenvalues.

LATEX, 15 pages

Cited by in corpus (5)

• Eigenfunctions of Unbounded Support for Embedded Eigenvalues of Locally Perturbed Periodic Graph Operators
• Irreducibility of the Bloch Variety for Finite-Range Schrödinger Operators
• On the eigenvalues for slowly varying perturbations of a periodic Schrödinger operator
• A Rellich Type Theorem for Discrete Schr{ö}dinger Operators
• Dislocation Defects and Diophantine Approximation