One of the top scientists at City University of Hong Kong (CityU) has been elected as a Fellow of the American Physical Society (APS) for his outstanding contribution to computational physics.

Professor Zhang Ruiqin of the Department of Physics at CityU was cited by APS “for path-breaking contributions to the development of quantum-mechanical many-body methods, as well as modelling and simulation of large electronic systems such as those with nanosurfaces, promoting their applications in the fields of environment, energy, biology and medicine”.

“I am honoured to be elected as a fellow of APS and grateful for CityU’s continuous support to my academic research.” said Professor Zhang, who joined CityU in 1997 and has committed to research into computational physics for years.

Computational physics is useful for studying quantum systems, such as how electrons move. “Previously it took us a long time to conduct experiments. But with computational approaches, we can simulate and predict some phenomenon, which helps to shorten the time for the whole experiments and provide good quality results,” he explained. Professor Zhang has developed a computation method that could save 70% of computational resources with the loss of negligible accuracy.

Professor Zhang has also pioneered many developments in the modelling and simulation of nanosurface systems. These developments help to promote applications of nanomaterials in the fields of environment, energy, biology and medicine. One of the most recent research achievements by his research team is the development of a vacuum-free thermal vapour condensation method for depositing high quality graphitic carbon nitride films, which is significant for photocatalysis, in particular photo-electrochemical water splitting to convert solar energy into hydrogen and oxygen, which are regarded as important energy sources for the future.

Another major achievement is his success in solving the Schr?dinger equation, which describes or predicts the behaviour of a quantum mechanical system, similar to the Newton’s law in classical mechanics, of many-electron systems without using any approximations. His works represents a breakthrough in the area of computational physics, because previously it was only possible to solve the Schr?dinger equation of a single hydrogen atom among the real systems exactly without using any approximations. 

The CityU physicist has received numerous accolades over the years: the State Natural Science Award (Third-class award) and the Scientific and Technological Development (First-class award) in 1997; the Friedrich Wilhelm Bessel Research Awards in 2004; and the State Natural Science Award (Second-class award) in 2005.

The APS Fellowship Programme recognises those who have made exceptional contributions to the physics enterprise through outstanding research, leadership or service, or the application of physics to science and technology. Each year, no more than 0.5% of the total APS membership is elected for Fellowship.