Spectral analysis of a class of Schroedinger operators exhibiting a parameter-dependent spectral transition
arXiv:1511.00097 · doi:10.1088/1751-8113/49/16/165302
Abstract
We analyze two-dimensional Schrödinger operators with the potential where and , which exhibit an abrupt change of its spectral properties at a critical value of the coupling constant . We show that in the supercritical case the spectrum covers the whole real axis. In contrast, for below the critical value the spectrum is purely discrete and we establish a Lieb-Thirring-type bound on its moments. In the critical case the essential spectrum covers the positive halfline while the negative spectrum can be only discrete, we demonstrate numerically the existence of a ground state eigenvalue.
20 pages, 4 figures