G.K. Avetisyan Department of Theoretical Physics, Erevan State University, ul. Aleko Monukyana, Erevan, 375049, Armenia
The authors of Ref. [1] drew incorrect conclusions when extending the results of Refs [2-14] on the stimulated one-photon Cherenkov effect and linear electromagnetic wave amplification, both for an infinite medium and for surface Cherenkov radiation in dielectric guides.