The authors demonstrate an electroabsorption modulator operating at 1.
55 mu m wavelength, which is integrated with passive waveguide gradual
ly tapered spotsize transformers allowing a low loss coupling to cleav
ed flat optical fibres. The modulator has 10.1dB total fibre to fibre
insertion loss with 15dB extinction ratio and 300 Angstrom spectral ra
nge. The modulator polarisation sensitivity is lower than 0.5dB.