NANOSYSTEMS: PHYSICS, CHEMISTRY, MATHEMATICS, 2016, 7 (2), P. 290–302
Boundary triples for Schrödinger operators with singular interactions on hypersurfaces
J. Behrndt – Institut für Numerische Mathematik, Technische Universität Graz, Steyrergasse 30, 8010 Graz, Austria; email@example.com
M. Langer – Department of Mathematics and Statistics, University of Strathclyde, 26 Richmond Street, Glasgow G1 1XH, United Kingdom; firstname.lastname@example.org
V. Lotoreichik – Department of Theoretical Physics, Nuclear Physics Institute CAS, 250 68 Rêz near Prague, Czech Republic; email@example.com
The self-adjoint Schrödinger operator Aδ,α with a δ-interaction of constant strength α supported on a compact smooth hypersurface C is viewed as a self-adjoint extension of a natural underlying symmetric operator S in L2(Rn). The aim of this note is to construct a boundary triple for S* and a self-adjoint parameter Θδ,α in the boundary space L2(C) such that Aδ,α corresponds to the boundary condition induced by Θδ,α. As a consequence, the well-developed theory of boundary triples and their Weyl functions can be applied. This leads, in particular, to a Krein-type resolvent formula and a description of the spectrum of Aδ,α in terms of the Weyl function and Θδ,α.
Keywords: Boundary triple, Weyl function, Schrödinger operator, singular potential, interaction, hypersurface.
PACS 02.30.Tb, 03.65.Db