Developing a tuneable ferroelectric nematic materials platform

Nematic liquid crystals are ubiquitous in our lives; we encounter them constantly thanks to their widespread use in display technology. The nematic liquid crystal state is characterised by the constituent molecules being oriented, on average, along some direction termed the director. Even when formed from polar molecules, there is no preference for pointing “up” or “down” along this direction and so the bulk nematic phase is typically apolar. 

Over a century ago, Max Born [1] speculated that a polar nematic fluid would exist if the molecular electric dipole moments are large enough that dipole-dipole interactions between molecules are sufficient to overcome thermal fluctuations. The push to develop apolar nematic liquid crystals in display technology, coupled with the absence of experimental proof of the existence of polar nematic phases, meant that Born’s conjecture was largely forgotten. 

In 2017 two materials were reported - RM734 [2] and DIO [3]– that are now understood to have polar nematic order and are ferroelectric, over a century after Born’s conjecture [4-6]. This so-called ferroelectric nematic (NF) phase displays a host of unique properties that cannot be easily replicated by other fluid systems: ferroelectricity [5], polar domains [7], strong non-linear optical response [7], unique electrooptics [8], to name a few [9]. However, realizing these properties requires an improvement in materials and our understanding of how formulation relates to bulk properties.

This project is experimental in nature, with potential for supporting experimental work with modelling and simulations as required. This project will deliver an NF materials platform that enables any property of interest to be tuned, and thus will become the ‘standard’ material used in the field for the coming years. You will work with novel NF materials developed at the University of Leeds, formulate multi-component mixtures, measure physical properties, analyse data, and build an understanding of the physics of the NF phase. This project is most suited to candidates with a background in Physics, Chemistry or Materials Science.

If you are interested in this project, and would like to find out more about the research topic or the PhD program at the University of Leeds, then please contact Dr Richard Mandle (r.mandle@leeds.ac.uk)