Q&A with Dr Zhang Rui on advancing local research on soft matter

28 June 2022

Dr Zhang Rui, an assistant professor at the Hong Kong University of Science and Technology has shown for the first time how liquid crystals could form the basic elements needed for logic operations, paving the way for a completely new kind of computer. The results, published on 23 February 2022 in Science Advances, are not likely to become transistors or computers right away, but the technique points the way towards devices with new functions in sensing, computing and robotics.

Zhang developed this theoretical approach while he was a postdoctoral fellow at the University of Chicago. He joined the Hong Kong University of Science and Technology in 2020.

Croucher caught up with Zhang to learn more about the research group he set up here.

You previously worked at Fudan University, the University of Chicago, and the City University of New York. What attracted you to moving to Hong Kong?

Hong Kong is a unique city embracing both western and oriental cultures. It has strong ties to many important countries, including China, the UK and US. Academically speaking, Hong Kong has strong potential in the field of computational soft matter physics. Many top scholars I know are based in Hong Kong, some of whom I’m collaborating with now.

Tell us a little bit about the research group you have created at HKUST. What makes it unique?

The overarching goal of the Computational Soft Matter Group is to harness soft materials, such as active matter, multiphase or porous media, liquid crystals, polymers, colloids, and mechanical metamaterials, to design next generation, autonomous materials and soft machines. Our group employs both traditional and emerging computational methods, including machine learning, to propose novel soft materials with nontraditional functionalities, features and dynamics.

One of our research areas is chiral active matter. Many biomaterials consist of chiral molecules. These non-equilibrium systems are modelled as active matter by physicists with the goal to build a physical framework to understand biological phenomena. However, the structural chirality of active matter is oftentimes overlooked. Therefore, we are exploring new phenomena from chiral active matter.

Our group is made up of postdoc, PhD, and MPhil students and our research is multidisciplinary, covering physics, biology, chemistry, materials science, chemical engineering, and mechanical engineering. We are different from many theoretical and computational groups in that most of our research projects involve collaborations with experimental partners around the world. Therefore, the theory and simulations developed by us often come with experimental evidence and support.

Your approach is likely to be useful in the field of soft robotics. How does Asia, specifically Hong Kong, measure in terms of the global research and development of soft robotics?

A: Soft robotics is a new and interdisciplinary research area that could lead to big changes in human-machine interactions and has a range of biomedical applications, including wearable devices, space exploration, 4D printing, energy harvesting, smart buildings, sensing and diagnosis, and etc.

This research direction in Asia, particularly in Hong Kong, has started to grow incrementally, particularly in medical schools and engineering schools. I encourage more inter-school and University-Industry interactions to nurture this research field in Hong Kong.