The present invention is a waveguide photodetector. In one embodiment, the waveguide photodetector includes a waveguide layer where light is guided or is confined and a detection layer formed on the waveguide layer where guided light is detected. Each of the waveguide layer and the detection layer allows for the guiding of no more than a single mode of light for a given polarization. In another embodiment, the waveguide photodetector includes a waveguide layer where light is guided or is confined, a detection layer formed on the waveguide layer where guided light is detected, a first electrical contact coupled to the detection layer, and a second electrical contact coupled to the detection layer. The first electrical contact and the second electrical contact are disposed in a spaced-apart, substantially parallel manner relative to each other.