The work has yielded detectors and modulators that demonstrate top performance for transmission and reception entirely through graphene devices, reaching world-record data rates for graphene devices (50 Gb/s for an electro-absorption modulator
Srinivasan et al., "Real-Time 100 Gb/s NRZ-OOK transmission with a silicon photonics GeSi electro-Absorption modulator
," in Proceedings of the 6th IEEE Photonics Society Optical Interconnects Conference, OI 2017, pp.
The new reflective electro-absorption modulator
(R-EAM) offers engineers a low insertion loss, low drive voltage optical modulator suitable for applications such as remote antennas and radio-over-fibre.
Since conventional electro-absorption modulator
integrated lasers (EML) or Mach-Zehnder modulators used in long-distance transmission are limited to a distance of around 80 km there has been demand for longer-range capability.
In the externally modulated links, the optical transmitter is based on a laser power source, typically a solid-state laser, such as Nd-YAG followed by a Mach-Zehnder modulator or an electro-absorption modulator
. The external modulator ExMOD is modeled in terms of a small signal equivalent circuit model, as shown in Figure 7.
The nanoelectronics research center imec, its associated lab at Ghent University (Intec), and Stanford University have demonstrated a compact germanium (Ge) waveguide electro-absorption modulator
(EAM) with a modulation bandwidth beyond 50 GHz.