Integrated SiGe electro-optical modulator based on PIN diode in the 5.5-10 µm wavelength range

This paper reports the experimental demonstration of the first PIN electro-optical modulator operating in a wide mid-IR wavelength range. Free carrier plasma dispersion effect is exploited in SiGe waveguides, showing high efficiency with extinction ratio up to 3 dB in depletion and 10 dB in injection schemes at 10 µm wavelength. High speed operation is demonstrated, reaching frequencies up to 1.5 GHz.