Monolithic silicon nitride electro-optic modulator enabled by optically-assisted poling

Area of Science:

• Photonics and Materials Science
• Integrated Optics

Background:

• Silicon nitride is a promising material for on-chip integrated photonics.
• Achieving a linear electro-optic (EO) effect in silicon nitride has been challenging due to its intrinsic properties.
• Recent work shows a linear EO effect can be induced by charge carrier displacement under high electric fields.

Purpose of the Study:

• To develop a low-temperature method for enabling linear electro-optic modulation in silicon nitride.
• To demonstrate optically-assisted poling of silicon nitride microring resonators.
• To characterize the performance of the resulting silicon nitride EO modulators.

Main Methods:

• Optically-assisted poling of a silicon nitride microring resonator at room temperature.
• Optimization of the optical poling process to induce second-order nonlinearity.
• Measurement of the effective second-order nonlinearity and high-speed EO response.

Main Results:

• Successful implementation of optically-assisted poling, avoiding high-temperature processing.
• Experimental achievement of a long-term effective second-order nonlinearity of 1.218 pm/V.
• Demonstration of a high-speed EO modulator with a 4 GHz bandwidth.

Conclusions:

• Optically-assisted poling is an effective technique for realizing linear EO modulation in silicon nitride.
• This method enables the development of compact, monolithic silicon nitride EO modulators.
• The results pave the way for advanced integrated optical signal processing.