On realization of the original Weyl-Titchmarsh functions by Shr\"odinger L-systems

We study realizations generated by the original Weyl-Titchmarsh functions $m_{\mathrm{\infty }}(z)$ and $m_{\alpha }(z)$. It is shown that the Herglotz-Nevanlinna functions $(-m_{\mathrm{\infty }}(z))$ and $(1\mathrm{/}{m}_{\mathrm{\infty }}(z))$ can be realized as the impedance functions of the corresponding Shr"odinger L-systems sharing the same main dissipative operator. These L-systems are presented explicitly and related to Dirichlet and Neumann boundary problems. Similar results but related to the mixed boundary problems are derived for the Herglotz-Nevanlinna functions $(-m_{\alpha }(z))$ and $(1\mathrm{/}{m}_{\alpha }(z))$. We also obtain some additional properties of these realizations in the case when the minimal symmetric Shr"odinger operator is non-negative. In addition to that we state and prove the uniqueness realization criteria for Shr"odinger L-systems with equal boun-dary parameters. A condition for two Shr"odinger L-systems to share the same main operator is established as well. Examples that illustrate the obtained results are presented in the end of the paper.