Helical-grating two-mode fiber spatial-mode coupler

Author

Poole, Craig D. ; Townsend, C.D. ; Nelson, Katherine T.

Author_Institution

AT&T Bell Lab., Homdel, NJ, USA

Volume

9

Issue

5

fYear

1991

fDate

5/1/1991 12:00:00 AM

Firstpage

598

Lastpage

604

Abstract

The authors investigate a helical-grating geometry for coupling the spatial modes in a two-mode fiber. The feasibility of making fiber grating filters based on this geometry is investigated. By adding mode strippers at the input and output of a helical-grating spatial-mode coupler, an optical notch filter is demonstrated with 0.3-dB waveguide loss, 24-dB extinction, and 24-nm spectral width. The effect of small ellipticity in the fiber core is also investigated, and it is shown that polarization-insensitive coupling can be achieved in a fiber with a sufficiently circular core

Keywords

diffraction gratings; fibre optics; optical couplers; optical losses; spatial filters; 0.3 dB; circular core; ellipticity; extinction; fiber core; fiber grating filters; helical-grating geometry; helical-grating spatial-mode coupler; input; mode strippers; optical notch filter; output; polarization-insensitive coupling; spectral width; waveguide loss; Fiber gratings; Fiber nonlinear optics; Optical fiber communication; Optical fiber couplers; Optical fiber devices; Optical fiber filters; Optical fiber polarization; Optical filters; Optical sensors; Optical waveguides;

fLanguage

English

Journal_Title

Lightwave Technology, Journal of

Publisher

ieee

ISSN

0733-8724

Type

jour

DOI

10.1109/50.79536

Filename

79536