Biaxial Nematic Liquid Crystals:reducing symmetry to increase order and develop novel applications

20世纪70年代和80年代液晶材料的发明和发展导致了现在非常成功的平板显示器行业，并允许开发各种便携式技术，包括膝上型计算机和移动的电话。这些技术成功的关键是功能材料的工程设计，以增强其在液晶显示器中的应用。显示器技术已经成熟，但现在液晶领域出现了令人兴奋的新发展，有望对未来技术产生重大影响。该建议提出了一种新的液晶，即所谓的双轴液晶系统。在这些系统中发生的对称性降低导致了许多潜在的影响，我们特别感兴趣的是探索它们在新的电光应用中的潜力（其可以包括可切换衍射光栅-对于光通信很重要）和非线性光学器件，因为材料是电可切换的，并且已经具有与有用的固态系统相当的非线性系数。我们在这里提出的研究将对这些材料做出重大贡献，这是几年前才发现的我们将攻击的一些关键问题，将允许双轴向列的使用，包括开发新的，较低的温度材料（目前的材料是双轴温度通常在150 ℃左右）和理解的双轴顺序通过互补的理论和实验方法的性质。因此，我们期望能够在上述应用中捕获和控制双轴有序，并推断出使用这些新材料的最佳机会。该计划汇集了来自多个学科的科学家，使几个重要问题能够同时进行研究，并允许每个学科领域相互补充，以实现最佳协同效应。该小组在共同努力推动液晶领域的进展方面有着良好的记录，这些进展已经对应用领域产生了影响。

The invention and development of liquid crystal materials in the 1970s and 80s led to the now hugely successful flat panel display industry, and allowed the development of all sorts of portable technology, including lap-top computers and mobile phones. The key to the success of these technologies has been the engineering of functional materials to enhance their application specifically to liquid crystal displays. The displays technology is mature, but there are now exciting, new developments in the area of liquid crystals that promise to have significant impact on future technologies. This proposal addresses one kind of new liquid crystal, the so-called biaxial nematic systems. The reduced symmetry that occurs in these systems results in many potential implications, and we are particularly interested in exploring their potential in new electro-optic applications (which may include switchable diffraction gratings - important for optical communications) and non-linear optics, since the materials are electrically switchable, and already have nonlinear coefficients comparable to useful solid-state systems.The research that we are proposing here will make a significant contribution to these materials, which were only discovered a few years ago. We will attack some of the key issues that will allow biaxial nematics to be used, including developing new, lower temperature materials (current materials are biaxial at temperatures often around 150C) and understanding the nature of the biaxial order through complementary theoretical and experimental approaches. Thus we expect to be able to capture and control biaxial order in the applications already described, and deduce the best opportunities for using these new materials.The programme brings together scientists from a number of disciplines, to enable several important issues to be examined simultaneously, and to allow each discipline area to feed into the other, for optimum synergy. The group has a strong record of working together to make advances in liquid crystals, which have already had impact on applications areas.