DISCRETE SPECTRUM OF CRANKED, BRANCHING, AND PERIODIC WAVEGUIDES

作者：Nazarov S A^*

来源：St Petersburg Mathematical Journal, 2012, 23(2): 351-379.

• Eigenvalues
• discrete spectrum
• Laplace operator
• cranked
• branching
• periodic waveguides

The variational method is applied to the study of the spectrum of the Laplace operator with mixed boundary conditions and with Dirichlet conditions in planar or multidimensional domains (waveguides) with cylindrical or periodic exits to infinity. The planar waveguides of constant width are discussed completely, such as cranked, broken, smoothly bent, or branching waveguides. For them, the existence of eigenvalues below the continuous spectrum threshold is established. A similar result is obtained for the multidimensional cranked and branching waveguides, and also for some periodic ones. Several open questions are stated; in particular, they concern problems with Neumann boundary conditions, full multiplicity of the discrete spectrum, and planar waveguides with piecewise constant boundary.

• 出版日期2012-4