Collaborative Research: Combinatorial solution processing of optical phase change materials

The University Of Central Florida Board Of Trustees, Orlando FL

Investigators

Abstract

Non-technical summary Phase change materials (PCMs) are a class of compounds whose optical properties undergo dramatic changes upon micro-structural transformation. This unique property allows novel PCM-based reconfigurable or programmable optical systems to be created. Unlike conventional optics whose characteristics are fixed, the functions of such programmable optics can be dynamically configured on-the-fly to adapt to changing application needs. This project, supported by the Ceramics program in the Division of Materials Research, pioneers a transformative synthesis paradigm for expedited discovery of PCM alloys, specifically tailored for optical applications. Instead of relying on traditional costly vacuum systems to prepare PCMs, the program explores solution-based printing – similar to color printing of photos – as a scalable synthetic route of PCMs. The researchers also develop new methods to enable high-throughput screening and down-selection of PCMs to achieve material properties optimized for specific optical applications. Fundamental insights gained from this research have broad impacts on applications spanning energy-efficient data communications, active metamaterial, photonic memory, reflective display, analog optical computing, and beyond. In addition, the project also enables research opportunities for undergraduate students at the University of Central Florida and the Massachusetts Institute of Technology. Furthermore, the researchers develop a massive open online course (MOOC) dedicated to glass materials, thereby filling a critical gap when it comes to glass science education. Technical summary Phase change materials (PCMs) are a class of compounds whose optical properties undergo dramatic changes upon micro-structural transformation. Discovery of new optical PCMs and characterization of their structural, optical, and phase transition properties, however, are increasingly becoming the bottleneck given the low throughput of traditional PCM synthesis and inability to reliably measure their properties in operando. With this project, supported by the Ceramics program in the Division of Materials Research, researchers at the University of Central Florida and the Massachusetts Institute of Technology develop a transformative synthesis and characterization paradigm for high-throughput discovery and characterization of multicomponent PCM alloys, specifically tailored for optical applications. Rather than relying on vacuum deposition, they harness combinatorial printing of PCM solutions to facilitate high-throughput, scalable synthesis of PCMs with custom chemistries and even complex multilayer structures. The PCMs are printed on integrated micro-heater arrays as a multifunctional characterization platform. It facilitates systematic investigation on the impact of post-deposition annealing and operando characterization of two critical attributes traditionally challenging to assess: temperature-dependent phase transition kinetics, and optical constants of thin film PCMs. Further coupled with a cohort of other characterization techniques commensurate with high-throughput screening, combinatorial solution processing presents a facile route for expedited discovery of new optical PCMs with broad impacts on energy-efficient data communications, active metamaterial, photonic memory, reflective display, analog optical computing, and beyond. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.