Electrically pumped Er-doped light emitting slot waveguides for on-chip optical routing at 1.54 μm

Optoelectronic properties of Er 3+ -doped slot waveguides electrically driven are presented. The active waveguides have been coupled to a Si photonic circuit for the on-chip distribution of the electroluminescence (EL) signal at 1.54 μm. The Si photonic circuit was composed by an adiabatic taper, a bus waveguide and a grating coupler for vertical light extraction. The EL intensity at 1.54 μm was detected and successfully guided throughout the Si photonic circuit. Different waveguide lengths were studied, finding no dependence between the waveguide length and the EL signal due to the high propagation losses measured. In addition, carrier injection losses have been observed and quantified by means of time-resolved measurements, obtaining variable optical attenuation of the probe signal as a function of the applied voltage in the waveguide electrodes. An electro-optical modulator could be envisaged if taking advantage of the carrier recombination time, as it is much faster than the Er emission lifetime.