High speed silicon photonic electro-optic Kerr modulation

TL;DR

This paper demonstrates high-speed silicon photonic electro-optic modulation using the Kerr effect, achieving 100 Gbit/s data rates and highlighting its potential for low-loss, phase-based optical communication.

Contribution

It provides the first high-speed demonstration of Kerr effect-based modulation in silicon PIN waveguides, quantifying Kerr and plasma effects and showing Kerr dominance at high electric fields.

Findings

Kerr effect dominates plasma dispersion in high electric fields

Achieved eye diagrams up to 100 Gbit/s in NRZ format

Demonstrated potential for low-loss, phase modulation in silicon

Abstract

Electro-optic silicon-based modulators contribute to ease the integration of high-speed and low-power consumption circuits for classical optical communications or quantum computers. However, the inversion symmetry in the silicon crystal structure inhibits the use of Pockels effect. An electric field-induced optical modulation equivalent to a Pockels effect can nevertheless be achieved in silicon by the use of DC Kerr effect. Although some theoretical and experimental studies have shown its existence in silicon, the DC Kerr effect in optical modulation have led to a negligible contribution so far. This paper reports demonstration of high-speed optical modulation based on the electric field-induced linear electro-optic effect in silicon PIN junction waveguides. The relative contributions of both plasma dispersion and Kerr effects are quantified and we show that the Kerr induced modulation is dominant when a high external DC electric field is applied. Finally, the high-speed modulation response is analyzed and eye diagram up to 100 Gbits/s in NRZ format are obtained. This work demonstrates high speed modulation based on Kerr effect in silicon, and its potential for low loss, quasi-pure phase modulation.