Theoretical Analysis of Efficient Thermo-Optic Switching on Si₃N₄ Waveguide Platform Using SiOC-Based...

Area of Science:

• Photonics and Materials Science
• Integrated Optics and Photonics
• Nanophotonics and Plasmonics

Background:

• Photonic integrated circuits (PICs) are vital for telecommunications, quantum computing, and biomedical applications.
• Silicon nitride (SiN) platforms offer transparency, low optical loss, and thermal stability for PICs.
• Efficient thermo-optic (TO) modulation on SiN is hindered by reconfigurability limitations and high power demands.

Purpose of the Study:

• To optimize TO phase shifters on SiN platforms for improved power efficiency, reduced footprint, and minimized insertion losses.
• To develop a CMOS-compatible plasmo-photonic TO phase shifter.
• To evaluate different interferometer architectures for superior performance.

Main Methods:

• Opto-thermal simulations were employed to assess four interferometer architectures: symmetric and asymmetric Mach-Zehnder Interferometers (MZIs), an MZI with a ring resonator, and a single-arm design.
• A plasmo-photonic TO phase shifter utilizing a SiOC material layer with a high TO coefficient and aluminum heaters on a SiN platform was introduced.
• Performance metrics including power consumption, insertion loss, footprint, and switching speed were evaluated.

Main Results:

• The asymmetric MZI with ring resonator (A-MZI-RR) architecture exhibited the best performance.
• The A-MZI-RR demonstrated minimal power consumption (1.6 mW) and low insertion loss (2.8 dB).
• The optimized device achieved a reduced length of 14.4 μm, presenting a favorable figure of merit.

Conclusions:

• Optimized SiN-based TO switches offer enhanced efficiency and compactness.
• The developed plasmo-photonic TO phase shifter supports scalable and energy-efficient PICs.
• These advancements are crucial for high-performance photonic applications demanding reduced power and size.