High performance, polarisation-independent semiconductor optical ampli
fiers based on low-tensile-strained separate confinement heterostructu
res and integrated with a double core taper have been realised. Fibre-
to-fibre gain as large as 29dB, with TE-TM polarisation sensitivity as
low as 0.3dB and an output saturation power of similar to 9dBm are cu
rrently achieved.