Heterogeneous integration of InP modulators on a silicon photonic platform, fabricated by bonding III–V wafer on patterned silicon waveguides, are proved to work between 77 K and 295 K. The performance of modulators based on the Franz-Keldysh effect (bulk) and the quantum confined Stark effect (quantum-well) is investigated for wavelengths ranging within 1460 nm–1580 nm. The bulk modulator is preferred when operating over a wide range of temperatures. The demonstration of such integrated optical components at low temperatures is especially attractive for applications that demand massive data communication between cryogenic and room temperatures requiring photonic interconnect, as well as applications with extreme environmental conditions, such as outer space exploration.
