Extremely low power consumption semiconductor optical amplifier gate for WDM applications

A polarisation insensitive semiconductor optical amplifier gate is reported. Very low current for fibre-to-fibre lossless operation (5.6-7.0 mA) and a high extinction ratio (>40 dB) were obtained over a wide wavelength range (1530-1560 nm), even when lensed fibres (5 dB loss/facet) were used.