Multi‐Level Electro‐Thermal Switching of Optical Phase‐Change Materials Using Graphene
Abstract
Reconfigurable photonic systems featuring minimal power consumption are crucial for integrated optical devices in real‐world technology. Current active devices available in foundries, however, use volatile methods to modulate light, requiring a constant supply of power and significant form factors. Essential aspects to overcome these issues are the development of nonvolatile optical reconfiguration techniques which are compatible with on‐chip integration with different photonic platforms and do not disrupt their optical performances. Herein, a solution is demonstrated using an optoelectronic framework for nonvolatile tunable photonics that uses undoped‐graphene microheaters to thermally and reversibly switch the optical phase‐change material Ge2Sb2Se4Te1 (GSST). An in situ Raman spectroscopy method is utilized to demonstrate, in real‐time, reversible switching between four different levels of crystallinity. Moreover, a 3D computational model is developed to precisely interpret the switching characteristics, and to quantify the impact of current saturation on power dissipation, thermal diffusion, and switching speed. This model is used to inform the design of nonvolatile active photonic devices; namely, broadband Si3N4 integrated photonic circuits with small form‐factor modulators and reconfigurable metasurfaces displaying 2π phase coverage through neural‐network‐designed GSST meta‐atoms. This framework will enable scalable, low‐loss nonvolatile applications across a diverse range of photonics platforms.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Nov 05, 2020
- Source ID
- 10.1002/adpr.202000034
Entities
People
- Carlos Ríos
- Christopher Roberts
- Haozhe Wang
- Hualiang Zhang
- Jeffrey B. Chou
- Jing Kong
- Juejun Hu
- Kathleen A. Richardson
- Mikhail Y Shalaginov
- Myungkoo Kang
- Sensong An
- Skylar Deckoff-jones
- Steven A. Vitale
- Tian Gu
- Vladimir Liberman
- Yifei Zhang
Organizations
- Defense Advanced Research Projects Agency
- Massachusetts Institute of Technology
- National Science Foundation
- University of Central Florida
- University of Massachusetts Lowell