We have extended the Gloge-Marcatili analysis to include the effect of a refractive-index dip in a multimode fiber characterized by a square-law profile. The analysis gives analytical expressions for the propagation characteristics and shows that the dip has a very significant effect on the impulse response.
© 1983 Optical Society of America
Ajoy K. Ghatak and Ramakant Srivastava, "WKB analysis of graded-index multimode fibers with a central-index dip," Appl. Opt. 22, 1763-1764 (1983)