Thermo-optic-enabled topological optimization for tunable ultra-compact silicon photonic device design

Area of Science:

• Photonics
• Materials Science
• Optical Engineering

Background:

• Topological inverse design methodologies are advanced for optical devices.
• Silicon permittivity's thermal dependency offers new design avenues for integrated photonics.

Purpose of the Study:

• To propose and validate a thermo-optic-enabled topological optimization methodology.
• To design ultra-compact optical switches with temperature actuation capabilities.

Main Methods:

• Utilizing topological optimization incorporating silicon's thermal permittivity.
• Experimental validation of the proposed methodology through an optical switch design.

Main Results:

• An ultra-compact optical switch (10 µm x 6 µm) was designed and validated.
• The switch operates in the C-band with <2 dB insertion loss and <14 dB extinction ratio.
• The device functions as a tunable power splitter with varying ratios (0:100 to 100:0) and stable 50:50 splitting over a 23 nm range.

Conclusions:

• Thermo-optic effects integrated with topological optimization enable novel compact photonic devices.
• The demonstrated switch offers significant size reduction and tunable functionality for integrated circuitry.