Abstract

Waveguide-integrated photonic modulators are crucial devices when encoding optical signals for electronic–photonic integration on silicon. Silicon photonic modulators based on the free carrier plasma dispersion effect have undergone significant development in recent years, reaching speeds of 40|[nbsp]|Gbit|[nbsp]|s–1 (ref.|[nbsp]|7). Some issues yet to be resolved include the large size and the relatively high energy consumption of silicon Mach–Zehnder interferometer modulators, and the susceptibility to fabrication errors as well as a limited operation wavelength range of |[sim]|1|[nbsp]|nm for silicon microring modulators. We demonstrate the first waveguide-integrated GeSi electro-absorption modulator on silicon with a small active device area of 30|[nbsp]||[micro]|m2, a 10-dB extinction ratio at 1,540|[nbsp]|nm, an operating spectrum range of 1,539–1,553|[nbsp]|nm, ultralow energy consumption of 50|[nbsp]|fJ per bit, and a 3-dB bandwidth of 1.2|[nbsp]|GHz. This device offers unique advantages for use in high-performance electronic–photonic integration with complementary metal oxide semiconductor circuits.