Resonant tunneling diode electroabsorption waveguide modulator operating at around 1550 nm

Summary form only given.The InGaAlAs/InP RTD-electroabsorption modulator (EAM) consisted of a unipolar InGaAlAs (1520 nm) ridge optical waveguide containing a double-barrier resonant tunneling diode (6 nm wide InGaAs quantum well and 2 nm thick AlAs barriers). The experimental set-up for measuring the DC electroabsorption response of the RTD-EAM consisted of an external cavity 1.5 /spl mu/m tunable diode laser which was fibre coupled to the RTD-EAM; the output from the RTD-EAM was fibre coupled to an optical power meter. DC characterisation of the electroabsorption response of the modulator shows a change in absorption of 5 dB for a 1 mV change in bias voltage within the NDR region of the RTD. This is an exceptionally low drive voltage for this amount of modulation. A total change in absorption of 13 dB was observed as the RTD-EAM biasing voltage was swept through the NDR region.