Opuscula Math. 41, no. 3 (2021), 413-435
https://doi.org/10.7494/OpMath.2021.41.3.413
Opuscula Mathematica
On the S-matrix of Schrödinger operator with nonlocal δ-interaction
Abstract. Schrödinger operators with nonlocal \(\delta\)-interaction are studied with the use of the Lax-Phillips scattering theory methods. The condition of applicability of the Lax-Phillips approach in terms of non-cyclic functions is established. Two formulas for the \(S\)-matrix are obtained. The first one deals with the Krein-Naimark resolvent formula and the Weyl-Titchmarsh function, whereas the second one is based on modified reflection and transmission coefficients. The \(S\)-matrix \(S(z)\) is analytical in the lower half-plane \(\mathbb{C}_{−}\) when the Schrödinger operator with nonlocal \(\delta\)-interaction is positive self-adjoint. Otherwise, \(S(z)\) is a meromorphic matrix-valued function in \(\mathbb{C}_{−}\) and its properties are closely related to the properties of the corresponding Schrödinger operator. Examples of \(S\)-matrices are given.
Keywords: Lax-Phillips scattering scheme, scattering matrix, \(S\)-matrix, nonlocal \(\delta\)-interaction, non-cyclic function.
Mathematics Subject Classification: 47B25, 47A40.
- V.M. Adamyan, Nondegenerate unitary couplings of semiunitary operators, Funct. Anal. Appl. 7 (1973), no. 4, 255-267.
- V.M. Adamyan, B.S. Pavlov, Null-range potentials and M.G. Krein's formula for generalized resolvents, J. Sov. Math. 42 (1988), 1537-1550.
- N.I. Akhiezer, I.M. Glazman, Theory of Linear Operators in Hilbert Spaces, Dover Publication Inc, New York, 1993.
- S. Albeverio, L. Nizhnik, Schrödinger operators with nonlocal point interactions, J. Math. Anal. Appl. 332 (2007), 884-895.
- S. Albeverio, L. Nizhnik, Schrödinger operators with nonlocal potentials, Methods Funct. Anal. Topology 19 (2013), no. 3, 199-210.
- S. Albeverio, R. Hryniv, L. Nizhnik, Inverse spectral problems for nonlocal Sturm-Liouville operators, Inverse Problems 23 (2007), 523-536.
- F. Bagarello, J.-P. Gazeau, F.H. Szafraniec, M. Znojil (eds.), Non-Selfadjoint Operators in Quantum Physics. Mathematical Aspects , J. Wiley & Sons, Hoboken, New Jersey, 2015.
- J. Behrndt, M.M. Malamud, H. Neidhardt, Scattering matrices and Dirichlet-to-Neumann maps, J. Funct. Anal. 273 (2017), 1970-2025.
- C.M. Bender, P.E. Dorey, T.C. Dunning, A. Fring, D.W. Hook, H.F. Jones, S. Kuzhel, G. Levai, R. Tateo, PT-Symmetry in Quantum and Classical Physics, World Scientific, Singapore, 2019
- J. Brasche, L.P. Nizhnik, One-dimensional Schrödinger operators with general point interactions, Methods Funct. Anal. Topology 19 (2013), no. 1, 4-15.
- K.D. Cherednichenko, A.V. Kiselev, L.O. Silva, Functional model for extensions of symmetric operators and applications to scattering theory, Networks and Heterogeneous Media 13 (2018), no. 2, 191-215.
- P.A. Cojuhari, S. Kuzhel, Lax-Phillips scattering theory for PT-symmetric \(\rho\)-perturbed operators, J. Math. Phys. 53 (2012), 073514.
- R.G. Douglas, H.S. Shapiro, A.L. Shields, Cyclic vectors and invariant subspaces for the backward shift operator, Ann. Inst. Fourier 20 (1970), 37-76.
- M. Gawlik, A. Główczyk, S. Kuzhel, On the Lax-Phillips scattering matrix of the abstract wave equation, Banach J. Math. Anal. 13 (2019), no. 2, 449-467.
- M.L. Gorbachuk, V.I. Gorbachuk, Boundary Value Problems for Operator Differential Equations, Kluwer, Dordrecht, 1991.
- S. Kuzhel, On the determination of free evolution in the Lax-Phillips scattering scheme for second-order operator-differential equations, Math. Notes 68 (2000), 724-729.
- S. Kuzhel, Nonlocal perturbations of the radial wave equation. Lax-Phillips approach, Methods Funct. Anal. Topology 8 (2002), no. 2, 59-68.
- S. Kuzhel, On the inverse problem in the Lax-Phillips scattering theory method for a class of operator-differential equations, St. Petersburg Math. J. 13 (2002), 41-56.
- S. Kuzhel, On conditions of applicability of the Lax-Phillips scattering scheme to investigation of abstract wave equation, Ukrainian Math. J. 55 (2003), 621-630.
- A. Kuzhel, S. Kuzhel, Regular Extensions of Hermitian Operators, VSP, Utrecht, 1998.
- S. Kuzhel, M. Znojil, Non-self-adjoint Schrödinger operators with nonlocal one-point interactions, Banach J. Math. Anal. 11 (2017), no. 4, 923-944.
- P. Lax, Translation invariant spaces, Acta Math. 101 (1959), 163-178.
- P. Lax, R. Phillips, Scattering Theory, Revised Edition, Academic Press, London, 1989.
- N.K. Nikolski, Operators, Functions, and Systems: an Easy Reading, Volume I, AMS, USA, 2002.
- M. Reed, B. Simon, Methods of Modern Mathematical Physics, Volume III: Scattering Theory, Academic Press, New York, 1979.
- K. Schmüdgen, Unbounded Self-adjoint Operators on Hilbert Space, Springer, Berlin, 2012.
- Anna Główczyk (corresponding author)
https://orcid.org/0000-0001-5205-827X
- AGH University of Science and Technology, Faculty of Applied Mathematics AGH, Al. Mickiewicza 30, 30-059 Kraków
- Sergiusz Kużel
https://orcid.org/0000-0002-4322-6611
- AGH University of Science and Technology, Faculty of Applied Mathematics AGH, Al. Mickiewicza 30, 30-059 Kraków
- Communicated by Alexander Gomilko.
- Received: 2020-09-01.
- Accepted: 2021-02-01.
- Published online: 2021-04-19.