Experimental demonstration of titanium nitride plasmonic interconnects

Area of Science:

• Plasmonics and Nanophotonics
• Materials Science
• Integrated Optics

Background:

• Plasmonic interconnects are crucial for miniaturizing optical devices.
• Existing materials often face challenges with CMOS compatibility and performance.
• Titanium nitride (TiN) offers a promising alternative due to its CMOS compatibility.

Purpose of the Study:

• To propose and experimentally investigate an insulator-metal-insulator plasmonic interconnect utilizing TiN.
• To evaluate the performance of TiN waveguides at telecommunication wavelengths.
• To theoretically analyze advanced TiN-based structures for improved plasmonic performance.

Main Methods:

• Fabrication and experimental characterization of TiN-based insulator-metal-insulator plasmonic waveguides.
• Measurement of propagation losses and mode size at 1.55 µm wavelength.
• Theoretical modeling of solid-state structures with Si3N4 superstrates and ultra-thin TiN metal strips.

Main Results:

• Achieved propagation losses below 0.8 dB/mm with a mode size of 9.8 µm for TiN waveguides on sapphire.
• Experimental results closely matched theoretical predictions.
• Theoretical analysis predicted attainable propagation losses below 0.3 dB/mm with a 9 µm mode size in optimized structures.

Conclusions:

• TiN is a viable plasmonic material for practical applications.
• The proposed TiN interconnects show potential for solid-state, integrated nano-optic, and hybrid photonic devices.
• Further optimization can lead to significantly enhanced plasmonic performance.