@Article{Lotoreichik2011, author = "Lotoreichik, Vladimir", title = "Singular continuous spectrum of half-line Schrödinger operators with point interactions on a sparse set", journal = "Opuscula Math.", year = "2011", volume = "31", number = "4", pages = "615--628", doi = "http://dx.doi.org/10.7494/OpMath.2011.31.4.615", url = "http://dx.doi.org/10.7494/OpMath.2011.31.4.615", abstract = "We say that a discrete set \(X = \{ x_n \}_{n\in \mathbb{N}_0}\) on the half-line \[0 = x_0 \lt x_1 \lt x_2 \lt x_3 \lt ... \lt x_n \lt ... \lt +\infty \] is sparse if the distances \(\Delta x_n = x_{n+1}- x_n\) between neighbouring points satisfy the condition \(\frac{\Delta x_n}{\Delta x_{n-1}} \to +\infty\). In this paper half-line Schrödinger operators with point \(\delta\)- and \(\delta'\)-interactions on a sparse set are considered. Assuming that strengths of point interactions tend to \(\infty\) we give simple sufficient conditions for such Schrödinger operators to have non-empty singular continuous spectrum and to have purely singular continuous spectrum, which coincides with \(\mathbb{R}_+\).", keywords = "half-line Schrödinger operators, \(\delta\)-interactions, \(\delta '\)-interactions, singular continuous spectrum", issn = "1232-9274" }