It's a solid . . . it's a liquid . . . it's a LIQUID CRYSTAL! Researchers at the University of Wisconsin-Madison Materials Research Science and Engineering Center are investigating how the unique properties of liquid crystals allow them to act as environmental sensors, detecting toxins in the environment. In this video, we give a brief overview of what liquid crystals are and how their properties can be utilized to improve the world.
Many solid materials have a crystal structure, with atoms that exist in a particular, organized arrangement. The degree of organization can vary among crystals, however. High-quality crystalline materials are the foundation of many familiar devices, such as integrated circuits and solar cells. A better understanding of these materials and how to produce them is important for developing new technologies.
There are many ways atoms can arrange microscopically to form crystalline materials. Interestingly, materials created from different arrangements of the same atoms may exhibit completely different physical and chemical properties. A method called thin film epitaxy allows scientists not only to fine-tune the properties of known materials, but also to generate completely new materials with structures and properties not found in nature.
A bit of stray moisture during an experiment tipped off scientists about the strange behavior of a complex oxide material they were studying—shedding light on its potential for improving chemical sensors, computing and information storage. In the presence of a water molecule on its surface, the layered material emits ultraviolet light from its interior.
Transparent conducting oxides are unusual but highly useful materials that combine transparency to visible light, similar to glass, with high electrical conductivity, similar to copper and other metals.