Controllable graphs with least eigenvalue at least -2

Citation

Cvetkovic D, Rowlinson P, Stanic Z & Yoon M (2011) Controllable graphs with least eigenvalue at least -2. Applicable Analysis and Discrete Mathematics, 5 (2), pp. 165-175. https://doi.org/10.2298/AADM110909022C

Abstract
Connected graphs whose eigenvalues are distinct and main are called controllable graphs in view of certain applications in control theory. We give some general characterizations of the controllable graphs whose least eigenvalue is bounded from below by - 2; in particular, we determine all the controllable exceptional graphs. We also investigate the controllable graphs whose second largest eigenvalue does not exceed 1.

Keywords
graph spectra; control theory; main eigenvalues; bounded eigenvalues

Journal
Applicable Analysis and Discrete Mathematics: Volume 5, Issue 2