Abstract: Fabrication of a photonic integrated circuit (PIC) including active elements such as a semiconductor optical amplifier (SOA) and passive elements such as a floating rib waveguide. Selective area doping through ion implantation or thermal diffusion before semiconductor epitaxial growth is used in order to define the contact and lateral current transport layers for each active device, while leaving areas corresponding to the passive devices undoped. InP wafers are used as the substrate which may be selectively doped with silicon.

Abstract: A PPM transmitter includes an optical clock generator for generating equally-spaced optical pulses with a sampling period T; an encoder for transforming an incoming waveform U(t) into a linear combination V(t) of U(t) and a delayed output V(t?kT) according to a rule V(t)=U(t)+aV(t?kT), where k is a positive integer, V(t) is voltage generated by the encoder and a is a coefficient; and an optical delay generator for delaying optical pulses generated by the optical clock generator in proportion to the voltage V(t), such that ?tn=bV(t), where b is another coefficient and where ?tn is the amount of delay imposed by the optical delay generator. The PPM transmitter functions with a PPM receiver for communicating data without the need to transmit or otherwise provide a clock signal. The PPM receiver decodes an original series of the delayed optical pulses Q(t) and a second series Q(t?ckT) delayed by ckT where c is a coefficient.

Abstract: Fabrication of a photonic integrated circuit (PIC) including active elements such as a semiconductor optical amplifier (SOA) and passive elements such as a floating rib waveguide. Selective area doping through ion implantation or thermal diffusion before semiconductor epitaxial growth is used in order to define the contact and lateral current transport layers for each active device, while leaving areas corresponding to the passive devices undoped. InP wafers are used as the substrate which may be selectively doped with silicon.