Plasmonic IQ modulators with attojoule per bit electrical energy consumption

TLDR

Coherent optical communications, offering the highest spectral efficiency and data capacity, rely on IQ electro‑optic modulators that encode both amplitude and phase, and ideally require energy‑efficient, ultra‑compact devices for high‑density integration. The authors aim to demonstrate compact IQ modulators fabricated on silicon that operate with sub‑1‑V driving electronics. These modulators feature a 4 × 25 µm × 3 µm active section and are driven by sub‑1‑V electronics. The devices consume only 0.07 fJ bit⁻¹ at 50 Gbit s⁻¹, 0.3 fJ bit⁻¹ at 200 Gbit s⁻¹, and 2 fJ bit⁻¹ at 400 Gbit s⁻.

Abstract

Abstract Coherent optical communications provides the largest data transmission capacity with the highest spectral efficiency and therefore has a remarkable potential to satisfy today’s ever-growing bandwidth demands. It relies on so-called in-phase/quadrature (IQ) electro-optic modulators that encode information on both the amplitude and the phase of light. Ideally, such IQ modulators should offer energy-efficient operation and a most compact footprint, which would allow high-density integration and high spatial parallelism. Here, we present compact IQ modulators with an active section occupying a footprint of 4 × 25 µm × 3 µm, fabricated on the silicon platform and operated with sub-1-V driving electronics. The devices exhibit low electrical energy consumptions of only 0.07 fJ bit −1 at 50 Gbit s −1 , 0.3 fJ bit −1 at 200 Gbit s −1 , and 2 fJ bit −1 at 400 Gbit s −1 . Such IQ modulators may pave the way for application of IQ modulators in long-haul and short-haul communications alike.