Comment on "Design of a broadband highly dispersive pure silica photonic crystal fiber".
In a recent paper, Subbaraman et al. [Appl. Opt. 46, 3263-3268 (2007)] reported a theoretical and numerical study of highly dispersive pure silica photonic crystal fiber supporting group-velocity dispersion exceeding -2x10(4) ps/nm/km. This Comment argues that the authors consider only one of two sides of the same coin by not taking the corresponding beating length into account.
Mortensen
Niels Asger
NA
Department of Photonics Engineering, Technical University of Denmark, Kongens Lyngby, Denmark. asger@mailaps.org