Dichroic Coupler Research Articles

Novel 0.98/1.55 μm dichroic coupler based on lithium niobate

Abstract A novel 0.98/1.55 μm dichroic coupler with high-extinction ratio and low insertion loss has been designed and implemented on LiNbO3 for Erbium-doped fiber amplifier applications. The design of dichroic coupler is based on a modified directional coupler structure with a single bend in each channel. Beam propagation method is used to analyze the coupler performance to get the optimal parameters for device design, such as channel width, titanium thickness, channel gap, and interaction length. Samples with the signal coupling ratio as high as 100% and pumping power ratio as high as 95% have been obtained.

Preservation of polarization orthogonality of counterpropagating waves through dichroic birefringent optical media: experiments

It was proven theoretically by the author (ibid., vol.27, p.1538-9, 1991) that the polarization orthogonality of counterpropagating waves is preserved in any linear reciprocal medium, even when it is dichroic. This property is now confirmed experimentally using a dichroic coupler and a birefringent Mach-Zehnder interferometer. >