A Sub‐Picojoule per Bit Integrated Magneto‐Optic Modulator on Silicon: Modeling and Experimental Demonstration

Integrated magneto‐optic (MO) modulators are an attractive but not fully explored alternative to electro‐optic (EO) modulators. They are current driven, structurally simple, and could potentially achieve high efficiency in cryogenic and room temperature environments where fJ bit−1 optical interfaces are needed. In this paper, the performance and energy efficiency of a novel MO modulator at room temperature are for the first time assessed. First, a model of the micro‐ring‐based modulator is implemented to investigate the design parameters and their influence on the performance. Then, a fabricated device is experimentally characterized to assess its performance in terms of bit rate and energy efficiency. The model shows efficient operation at 1.2 Gbps using a 16 mA drive current, consuming only 155 fJ bit−1. The experimental results show that the MO effect is suitable for modulation, achieving error‐free operation above 16 mA with a power consumption of 258 fJ bit−1 at a transient limited data rate of 1.2 Gbps. Integrated magneto‐optic modulators are an attractive but not fully explored alternative to electro‐optic modulators. This paper assesses the performance at room temperature using a model and by characterizing a fabricated device. With an efficiency of 258 fJ bit−1, these modulators are not only current driven and structurally simple, they also have the potential to be used in efficient interconnects.