Air-silica microstructure fiber based variable optical attenuator device

We demonstrated an all-fiber variable attenuator using a tapered ASME Efficient modal field interaction between the propagating mode and tunable materials infused into the air-holes of the fiber results in a dynamic range of 30 dB, insertion loss 0.8 dB, and polarisation dispersion loss (PDL) of 0.5 dB. Further analysis of the device design, including optimization of polymer index, device length and taper diameter should result in reduced insertion loss and increased dynamic range.