Applied Physics Seminar
Abstract:
Light-matter interactions play a critical role in probing and manipulating fundamental building blocks in the physical world, such as electrons, photons, phonons and ions. Such interactions exist in various important energy processes. In this talk I will present two examples on how to utilize light-matter interaction to characterize and manage energy materials and devices. In this first example, a nonlinear stimulated Raman scattering microscopy is deployed to probe bond vibrations in ions in electrolytes, which is three orders of magnitude faster than conventional spontaneous Raman scattering. Such high speed and high sensitivity enable in-operando visualization of ion transport in battery electrolytes and its interaction with solid electrodes, which is difficult to be achieved by other means. Such dynamic imaging unveils new information on how electrolyte and electrode interacts with each other. In the second example, light-matter interaction is controlled by designing porous materials to realize high solar reflectance and high thermal emittance simultaneously, which leads to excellent performance in electricity-free sub-ambient radiative cooling technologies.
References:
- Cheng, Q et al., Operando and Three-Dimensional Visualization of Anion Depletion and Lithium Growth by Stimulated Raman Scattering Microscopy, Nature Communications, 9, 2942 (2018)
- Mandal, J et al., Hierarchically porous polymer coatings for highly efficient passive daytime radiative cooling. Science, 362, 315-319 (2018).
About the Speaker:
Dr. Yuan Yang is currently an associate professor of materials science in the department of applied physics and applied mathematics at Columbia University. He received his B.S. in physics at Peking University in 2007, followed by the completion of his Ph.D. in materials science and engineering at Stanford University in 2012. After graduation, he spent three years in the department of mechanical engineering at MIT, until joining Columbia in 2015. Dr. Yang's research interests include advanced energy storage and thermal energy management. He has published over 70 peer-reviewed papers with a citation over 20,000 times. He won Young Innovator Award by Nano Research in 2019. He is a Scialog fellow on Advanced Energy Storage.