Design of an electric-driven nonvolatile low-energy-consumption phase change optical switch

Area of Science:

• Photonics
• Materials Science
• Electrical Engineering

Background:

• Traditional optical switches (Si, SiN) suffer from high energy consumption and large footprints due to weak thermo-optic/electro-optic effects.
• Need for efficient, compact optical switches for large-scale integration in photonic chips.

Purpose of the Study:

• To develop and characterize an electric-driven phase change optical switch.
• To demonstrate low energy consumption and high performance for integrated photonic applications.

Main Methods:

• Fabrication of an optical switch using a Silicon waveguide, Ge2Sb2Te5 (GST) thin film, and a graphene heater.
• Utilized distinct voltage pulses (1.4 V SET, 4 V RESET) to induce reversible phase transitions in GST.
• Performed optical performance testing across a wide spectral range (1525-1575 nm).
• Conducted thermal simulations to evaluate energy consumption.

Main Results:

• Achieved high extinction ratio (44-46 dB) and significant optical property variations (Δneff = 0.49, Δα = 15 dBμm⁻¹).
• Demonstrated low energy consumption: 3.528 pJ for SET (1.4 V, 5 ns) and 1.05 nJ for RESET (4 V, 1.5 ns).
• Graphene's high thermal conductivity contributed to efficient thermal management.

Conclusions:

• The electric-driven phase change optical switch shows promise for large-scale integration and high-speed applications.
• The design facilitates analysis of thermal-conduction phase transitions in on-chip optical switches.
• Low energy consumption is crucial for the practical application of integrated photonic chips.