Comment on "Defocusing complex short-pulse equation and its multi-dark-soliton solution".

In their recent paper, Feng et al. [Phys. Rev.

Ultrashort optical waveguide excitations in uniaxial silica fibers: elastic collision scenarios.

In this work, we investigate the dynamics of an uniaxial silica fiber under the viewpoint of propagation of ultimately ultrashort optical waveguide channels. As a result, we unveil the existence of three typical kinds of ultrabroadband excitations whose profiles strongly depend upon their angular momenta. Looking forward to surveying their scattering features, we unearth some underlying head-on scenarios of elastic collisions.