Topological edge states in the Su-Schrieffer-Heeger model subject to balanced particle gain and lossMarcel Klett, Holger Cartarius, Dennis Dast, Jörg Main and Günter WunnerEur. Phys. J. D, 72 12 (2018) 214DOI: https://doi.org/10.1140/epjd/e2018-90502-3