Electronic Journal of Differential Equations (Sep 2018)
Exponential estimates for quantum graphs
Abstract
The article studies the exponential localization of eigenfunctions associated with isolated eigenvalues of Schrodinger operators on infinite metric graphs. We strengthen the result obtained in [3] providing a bound for the rate of exponential localization in terms of the distance between the eigenvalue and the essential spectrum. In particular, if the spectrum is purely discrete, then the eigenfunctions decay super-exponentially.