79 citations · 501 across the 68 of their papers we have counts for
82 papers
Revisiting the Weak Coupling Phenomenon for Two-Dimensional Schrödinger Operators
Jussi Behrndt, Petr Siegl, Nicolas Weber
We study the existence of negative eigenvalues for two-dimensional Schrödinger operators with real-valued potentials in the weak coupling regime. In his pioneering paper [Simon 197…
On non-negative operators in Krein spaces and their perturbations
Jussi Behrndt, Friedrich M. Philipp, Carsten Trunk
One of the most important contributions of Heinz Langer in the area of operator theory in Krein spaces is the introduction of the notion of definitizable operators and the construc…
Weak coupling for Schrödinger operators with complex potentials
Jussi Behrndt, Markus Holzmann, Petr Siegl +1
We study the discrete eigenvalues emerging from the threshold of the essential spectrum of one or two-dimensional Schrödinger operators with complex-valued -potentials in a…
On Sesquilinear Forms for Lower Semibounded (Singular) Sturm-Liouville Operators
Jussi Behrndt, Fritz Gesztesy, Seppo Hassi +2
Any self-adjoint extension of a (singular) Sturm-Liouville operator bounded from below uniquely leads to an associated sesquilinear form. This form is characterized in terms of pri…
Approximation of Dirac operators with -shell potentials in the norm resolvent sense, II. Quantitative results
Jussi Behrndt, Markus Holzmann, Christian Stelzer-Landauer
This paper is devoted to the approximation of two and three-dimensional Dirac operators with combinations of electrostatic and Lorentz scalar -shell inte…
Generalized boundary triples for adjoint pairs with applications to non-self-adjoint Schrödinger operators
Antonio Arnal, Jussi Behrndt, Markus Holzmann +1
We extend the notion of generalized boundary triples and their Weyl functions from extension theory of symmetric operators to adjoint pairs of operators, and we provide criteria on…