21 citations · 81 across the 8 of their papers we have counts for
8 papers
On Open Scattering Channels for a Branched Covering of the Euclidean Plane
Rainer Hempel, Olaf Post
We study the interaction of two scattering channels for a simple geometric model consisting in a double covering of the plane with two branch points, equipped with the Euclidean me…
Bound States for Nano-Tubes with a Dislocation
Rainer Hempel, Martin Kohlmann, Marko Stautz +1
As a model for an interface in solid state physics, we consider two real-valued potentials and on the cylinder or tube $S=\mathbb R \times (\mathbb R/\mathbb Z)…
L_1-Estimates for Eigenfunctions of the Dirichlet Laplacian
Michiel van den Berg, Rainer Hempel, Juergen Voigt
For and an open set in , we consider the eigenfunctions of the Dirichlet Laplacian of . If is associated with an eigenvalue belo…
On Open Scattering Channels for Manifolds with Ends
Rainer Hempel, Olaf Post, Ricardo Weder
In the framework of time-dependent geometric scattering theory, we study the existence and completeness of the wave operators for perturbations of the Riemannian metric for the Lap…
Dislocation problems for periodic Schrödinger operators and mathematical aspects of small angle grain boundaries
Rainer Hempel, Martin Kohlmann
We discuss two types of defects in two-dimensional lattices, namely (1) translational dislocations and (2) defects produced by a rotation of the lattice in a half-space. For Lipsch…
Spectral Properties of Grain Boundaries at Small Angles of Rotation
Rainer Hempel, Martin Kohlmann
We study some spectral properties of a simple two-dimensional model for small angle defects in crystals and alloys. Starting from a periodic potential , we le…