John Sandford O'Neill

My DPhil project brings together laser micro-machining and the science & technology of liquid crystals & polymers. I use a titanium-sapphire femtosecond laser to create microscale polymer structures directly inside electrically-controlled liquid crystal devices. This is of considerable scientific interest as it opens-up a new parameter for creating photonic structures with a locally-varying refractive index. It is also of interest from a commercial/industrial perspective as it can be used to design better liquid crystal displays and optical devices.

My research interests include:

• Liquid Crystal Photonics
• Augmented Reality/ Virtual Reality (AR/VR)
• 3D printing
• Laser fabrication and nanoprinting
• Soft robotics and micromechanical systems

Sandford O’Neill, J. J., Salter, P. S., Booth, M. J., Elston, S. J., Morris, S. M., “Electrically-tunable positioning of topological defects in liquid crystals.” Nature Communications, 11, 2203 (2020)

Sandford O’Neill, J. J., Fells, J. A. J., Welch, C., Mehl, G., Yip, W. C., Wilkinson, T. D., Booth, M. J., Elston, S. J., Morris, S. M., “Robust measurement of flexoelectro-optic switching with different surface alignments.” Journal of Applied Physics, 125, 093104 (2019).

Tartan, C. C., Sandford O’Neill, J. J., Salter, P. S., Aplinc, J., Booth, M. J., Ravnik, M., Morris, S. M., Elston, S. J., “Read on demand images in laser-written polymerizable liquid crystal devices.” Advanced Optical Materials, 6, 1800515 (2018).

• Leslie H. Paddle Scholarship (IET - Institution of Engineering and Technology), 2019
• European Forum Alpbach Scholarship 2019 (EFA - European Forum Alpbach), 2019
• Oxford Photonics Day Best Poster Prize (Oxford Photonics Network), 2018
• SPIE Photonics West Travel Award (SPIE - International Society for Optics & Photonics), 2018
• Diamond Light Source Science Communicators Award (Diamond Light Source), 2014

Sandford O’Neill, J. J., Salter, P. S., Booth, M. J., Elston, S. J., Morris, S. M., “Electrically-tunable positioning of topological defects in liquid crystals.” Nature Communications, 11, 2203 (2020) https://www.nature.com/articles/s41467-020-16059-1

Accompanying blog post:

https://chemistrycommunity.nature.com/channels/1465-behind-the-paper/posts/66317-bringing-order-to-disorder-topological-defects-in-liquid-crystals

News article:

https://eng.ox.ac.uk/news/bringing-order-to-disorder-in-liquid-crystals/