Optical power transfer in vertically integrated impedance-matched waveguide/photodetectors: physics and implications for diode-length reduction

We identify the physical basis of the irregular absorption (spatial transients) observed in vertically integrated and impedance-matched waveguide/photodiodes using numerical simulations. We then show how the mechanism underlying these transients can be exploited to design diodes 500% shorter than conventional evanescently coupled waveguide/photodiodes, in order to achieve low capacitance and high-speed operation.