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Low Energy Switching of Phase Change Materials Using a 2D Thermal Boundary Layer
Jing Ning1,2, Yunzheng Wang1, Ting Yu Teo1
1Singapore University of Technology and Design (SUTD), 8 Somapah Road, 487372 Singapore.
ACS Applied Materials & Interfaces
|August 31, 2022
Summary
Researchers improved energy efficiency in phase change materials (PCMs) for reconfigurable photonic devices. Inserting 2D materials like MoS2 or WS2 significantly reduces laser power needed for phase transitions, enhancing device performance.
Area of Science:
- Materials Science
- Photonics
- Nanotechnology
Background:
- Phase change materials (PCMs) offer switchable optical and electrical properties for reconfigurable photonic devices.
- Current applications require high-power heat pulses for PCM phase transitions, limiting energy efficiency, especially in silicon photonics due to high thermal conductivity.
Purpose of the Study:
- To enhance the energy efficiency of laser-induced phase transitions in PCMs for photonic applications.
- To investigate the use of 2D materials as thermal barriers to reduce energy consumption.
Main Methods:
- Incorporation of 2D materials (MoS2 or WS2) between the substrate (silica or silicon) and the PCM layer.
- Laser-induced phase transition experiments to measure power requirements.
- Thermal simulations to analyze heat confinement and energy transfer.
- Waveguide simulations to assess optical performance impact.
Main Results:
- The insertion of 2D MoS2 or WS2 layers reduced the required laser power for amorphization (RESET process) by at least 40%.
- Thermal simulations confirmed that 2D layers act as effective thermal barriers, confining heat within the PCM layer, comparable to a ~100 nm SiO2 layer.
- Waveguide simulations showed no degradation in optical performance or impact on the propagating mode in silicon waveguides.
Conclusions:
- 2D materials effectively improve the energy efficiency of laser-induced phase transitions in PCMs by acting as thermal barriers.
- This approach offers a simple, high-impact method to enhance PCM-tuned silicon photonic devices without compromising optical performance.
- The findings enable the development of more energy-efficient reconfigurable photonic devices.
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