On electromagnetic wave propagation in an optical fiber having a core radius with a periodic axial variation

✍ Scribed by Sangeeta Sinha; P. Khastgir; S. P. Ojha; P. K. Choudhury

• Publisher: John Wiley and Sons
• Year: 1996
• Tongue: English
• Weight: 485 KB
• Volume: 11
• Category: Article
• ISSN: 0895-2477
• DOI: 10.1002/(sici)1098-2760(19960420)11:6<335::aid-mop13>3.0.co;2-5

✦ Synopsis

A study is made of the modal properties of elechomagnetic waues propagating along a dielectric fiber hauing a periodically varying core cross-sectional size along the direction of propagation. The maximum variation of the core radius is assumed to be small, and a full cycle of variation occurs ouer a large change in the axial variable z compared with the core radius. The general characteristic equation and cutoff conditions are derived, assuming that the component of the propagation uector p along the axis caries with the axial coordinate z. In general, p is complex, showing an attenuation or a reinforcement because of alternate pair and constriction. As an illustration, a numerical estimate of d p / d z as a fLanction of z is made for some modes with simple a d special properties where attenuation is negligible, and the aria1 electric and magnetic jelds are in phase. The method can easily be extended to include more general cases by means of straightfonvard but tedious numerical work.