Shiun-Jr Yang is currently a 4th year PhD student in chemistry in the Fleming group, where he studies energy transfer dynamics in natural photosynthetic systems. He grew up in Taiwan and received a B.S. and a M.S. in chemistry from National Taiwan University before coming to UC Berkeley.
Shiun-Jr’s work focuses on combing both experimental and theoretical techniques to understand how solar energy conversion happens in nature. Light-harvesting in plants involves many different chlorophyll-binding proteins, forming a complex energy transfer network. Not only does this network allow efficient solar energy conversion, but it also provides a means to save the plants from photodamage when exposed to extreme sunlight. However, the functional role of each individual protein and the design principle of the system are still unclear due to the large number of chlorophylls involved, which makes the system extremely difficult to study. Recent advancement of Two-Dimensional Electronic-Vibrational Spectroscopy, first developed in the Fleming group, has provided enhanced resolution that allows detailed information of the ultrafast dynamics to be obtained. This opens up new possibilities for the studies of larger systems, but also challenges our ability to extract information from the 2D spectra that contain a great amount of detail. Therefore, it is crucial to combine experimental and theoretical techniques to achieve better understanding of the complex energy transfer network. Based on the newest knowledge of the photosynthetic system as well as kinetic theories, we can construct a model that describes the energy transfer network. Combining the model with our experimental results, we are aiming to gain further understanding of natural photosynthesis and apply the knowledge to the future design of efficient and durable solar energy devices.