Polarization-independent all-fiber wavelength-division multiplexer based on a Sagnac interferometer

Abstract

An all-fiber wavelength-division multiplexer (WDM) based on the nonreciprocity of the birefringence to the polarization states is proposed. The transfer function of a Sagnac interferometer is wavelength dependent if the loop birefringence of the interferometer consists of both circular and linear parts. Theoretical analysis shows that the output characteristics of this WDM are similar to those of a fiber taper-based device. Both the bandwidth and the peak wavelength of the new WDM can be tuned by changing the loop birefringence. Experimental prototypes exhibit a channel isolation greater than 25 dB with peak passband insertion loss of less than 1 dB.

Stable and broad bandwidth multiwavelength fiber ring laser incorporating a highly nonlinear photonic crystal fiber

“…In order to make the power distribution over different channels nearly uniform, a Sagnac loop filter [7] with a transmission spectrum that is a mirror image of the laser output spectrum is designed and inserted at the laser output to flatten its spectrum [shown in Fig. 2(b)].…”

Performance of Sagnac Interferometer with Loops Made of PCF and PANDA Fibers

“…As of today, several components based on SLI, have been designed for applications of wavelength division multiplexing (WDM) filters and optical sensors, using conventional and photonic crystal fibers [3][4][5][6]. In an SLI, two interfering waves in an optical fiber loop counter-propagate in a similar path.…”

Photonics Crystal Fiber Loop Mirrors and Their Applications'

“…Many components based on FLMs have been demonstrated for applications in wavelength-division-multiplexing filters and in sensors, among others [3][4][5][6][7]. In FLM, the two interfering waves counter-propagate through the same fiber and are exposed to the same environment.…”