Professor Helen F. Gleeson

Profile

I attended Holy Family Comprehensive School in Keighley as a teenager. I then moved to Manchester and graduated with a 1st class Joint Honours degree in Maths and Physics from Manchester University in 1983. I undertook an industrially sponsored experimental PhD in the optics of liquid crystals having been inspired by an undergraduate lecture course, gaining my PhD in 1986. I spent three years in a rather unusual postdoc role, running an industrially funded research unit at Manchester, an experience that shaped my academic career during which I’ve continued to interact with industry. I joined the academic staff in Physics at Manchester in 1989 as their first female lecturer, and subsequently held a number of posts in the University, including Associate Dean for Research in the Faculty of Engineering and Physical Sciences (2002-2007) and Head of the School of Physics and Astronomy (2008-2010). In 2015, I moved to Leeds as Cavendish Professor and the head of the Soft Matter Physics Group and was Head of School from 2016-2021. 

My research has always involved liquid crystals and in addition to carrying out fundamental studies of the physics of these materials, I have invented several novel applications, most recently switchable contact lenses.

I have published >180 journal papers and given >350 conference presentations. I have been awarded the British Liquid Crystal Society Hilsum and GW Gray Medals (2006 & 2013), the 2012 Holweck Prize and Medal of the Institute of Physics and Société Française de Physique, and the Rank Prize Lecture recognising my research. I was awarded an OBE for Services to Science in 2009, for my work in outreach, in particular encouraging women to study physics.  In 2018, I won the Times Higher Education award for 'Outstanding Research Supervisor of the Year'.

Responsibilities

• Head of Soft Matter Physics

Research interests

My research concerns self-ordering and self-assembling materials, particularly liquid crystal phases. I'm an experimentalist and use a variety of approaches to understand liquid crystal structures - I aim to determine how the nanoscale properties of complex molecules affect their macroscopic physics.

Much of my work has involved understanding liquid crystal systems with reduced symmetry (for example chiral or biaxial phases), both in the bulk and in devices. I have investigated biological systems as well as synthetic liquid crystal materials and an important part of my research is to understand how liquid crystals can be used for novel photonic devices and applications. I have developed novel experimental techniques to study these complex, self-organising materials and optically active media. The new experimental approaches I have developed include time-resolved and resonant x-ray scattering at synchrotrons and a variety of optical and electro-optical measurements (Raman scattering, Kerr effect etc.). These allow a deep insight into systems that show ferroelectric, ferrielectric and antiferroelectric properties, blue phases and unusual nematic systems.

Liquid crystals are perhaps best known for their use in display devices and I'm very interested in developing new applications. I produced the first graphene-based liquid crystal device in collaboration with the Profs. Geim and Novoselov, who won the Nobel Prize for their discovery of graphene. I have worked on light sensitive (photochromic) materials and laser tweezers for transferring the angular momentum from light to liquid crystal droplets. Using liquid crystal physics to inform the study of biological systems provides a very powerful approach to understanding complex systems, for example the methodology normally used to predict the optics of liquid crystal devices provided a physiologically realistic mechanism for the perception of polarized light in vertebrates. Some recent work on devices has led to the invention of switchable contact lenses in which the voltage-induced change in refractive index of the liquid crystal lens element causes a change in focus, equivalent to putting on reading glasses; this is now being developed in a spin out company 'Dynamic Vision Systems Ltd.'. Liquid crystals are intriguing and fun with much scope for both challenging fundamental physics and inventive new devices.

My current interests continue to include novel liquid crystal phases and non-display applications of liquid crystals. My current projects involve a few quite different areas: liquid crystal elastomers; switchable liquid crystal microdroplets for biosensors; and liquid crystals for THz applications. Our work on elastomers led to the recent discovery of their auxetic behaviour, making them the first synthetic molecular auxetic materials. Formally, this property is known as 'negative Poisson ratio', but more simply it means that the materials get thicker (rather than thinner) when stretched. Such materials are expected to have wide application in areas as  diverse as biomaterials, aerospace, defence and acoustics. The biosensor work has seen fast, responsive switching of micron-sized droplets of LCs, with the potential to give an optical indication of the presence of toxins. Our work on THz applications involves and exciting collaboration with engineers.

Qualifications

• BSc (Joint Hons) Mathematics and Physics
• PhD Physics
• OBE
• FInstP

Professional memberships

• Institute of Physics (Fellow)

Student education

I have always enjoyed teaching. As Head of School I have had overall responsibility for teaching within the School. I have personally carried out a wide  range of teaching including 1^st year level mathematics for physicists, specialist M-level courses in Soft Matter, undergraduate courses in optics. I have also always taken a great interest in teaching practical skills to physicists, inventing several new undergraduate experiments during my career. During lockdown I devised ‘take home’ experiments that allowed students to investigate the optical properties of birefringent materials, particularly liquid crystals, doing safe, hands-on experiments at home – a change from simple remote teaching.

Current postgraduate researchers

• Zhenming Wang
• Emily Cooper
• Diana Nikolova
• Aidan Street