Abstract

Long period fiber gratings that couple light from guided core modes to non-guided cladding modes provide a means of introducing wavelength dependent losses in optical fiber systems.¹ As a result, these in-fiber devices have found use as gain-equalizers in broadband optical fiber amplifiers,² as band-rejection filters in high-power cascaded Raman fiber lasers and amplifiers,³ and as stabilizers in 980 nm pump diodes.⁴ In addition, the ability to access the cladding mode has rendered them sensitive to external perturbations such as temperature, pressure and refractive-index with obvious applications as sensors.⁵, ⁶ In this review, we highlight recent results and describe some of the key spectral and thermal properties of long-period fiber gratings.

© 1997 Optical Society of America