In this new lab we are interested in the study of liquid crystals. These fascinating materials share some properties of liquids and some properties of solids: they can flow like liquids but their components can orient in space along a uniform direction, like solids. Their orientation can be manipulated in many ways and this give rise to many interesting effects. Our research will develop in two main directions.
Optics of liquid crystal defects
Liquid crystals are widely used in LC displays when they are “well-behaved”, i.e. when they are uniformly aligned. However in some cases the boundaries may prevent their spontaneous alignment. In this case liquid crystals form topological defects, small regions where they are disordered. While topological defects are a common feature across many fields in physics, liquid crystals are quite unique in the sense that defects can be seen and detected just using optical microscopy.
Defects can interact with light in interesting ways and they can be used to form self-assembled micro-lasers, resonators or lenses (see for example: Serra, Gharbi et al., Adv. Opt. Mater. 2013).This interaction, in turn, can shed light to the nature of the defect itself.
We are interested in looking at various types of liquid crystals and find a “catalogue” of possible optical components made of reconfigurable and moldable liquid crystal defects.
These are some examples of systems we are looking at:
- defects at the smectic to chiral nematic phase transitions in confined geometries
- regular arrays of defects in nematics and smectics
- liquid crystal blue phases
Liquid crystal elastomers for living cells
Mammalian cells are very sensitive to the environment that surround them. We intend to study their interaction with liquid crystal elastomers, made of liquid crystals crosslinked into polymeric networks. These materials still retain many properties of the liquid crystal phase, combined with those of rubbery materials. These characteristic make them ideal to study the response of cells to molecular order.