Phase change materials in light modulating applications beyond data storage
Wright, C. David
The use of phase change materials in applications that manipulate light reflectivity and transmissivity would appear to be both obvious and completely infeasible at the same time. It is obvious simply because many of these materials were developed with the primary aim of being able to store optically accessible data, which relied on the optical refractive index contrast between the two reversibly accessible solid states of the material. It would appear infeasible upon further consideration because, not only is the change in the refractive index not very large in the visible wavelengths, but also because the absorption of the material in both states resembles a metallic element as opposed to a dielectric, which would greatly reduce contrast. Over the last two and a half years, we have combined thin film optics concepts with phase change materials to essentially enable the use of such materials in light modulation applications such as displays, smart glazing and security markings. In this abstract, we also show some additional work done on two types of phase change materials, demonstrating that new areas of technological development for phase change materials are perhaps in some ways even more exciting than existing ones.
Invited paper presented at the European\Phase Change and Ovonics Symposium 2015, 2015-09-06, 2015-09-08, Amsterdam
European\Phase Change and Ovonics Symposium 2015, 2015-09-06, 2015-09-08, Amsterdam