Ge0.6Si0.4 rib waveguide avalanche photodetectors for 1.3 μm operation

Abstract

Performance of strained‐layer superlattice Ge_0.6Si_0.4 waveguide avalanche photodetectors is evaluated for optical fiber applications at 1.3 μm. These devices are grown on Si substrates by molecular beam epitaxy. Waveguiding is accomplished by means of a 1.5–1.8‐μm‐thick Si rib waveguide which provides an effective index step of δn=8×10⁻³. The detector response bandwidth exceeds 8 GHz at a gain of 6. A receiver sensitivity of ηP̄=−29.4 dBm has been obtained at the data rate of 800 Mb/s with the corresponding error‐free transmission over 45 km of single mode fiber.