Join us in the IAS STEM Graduate Colloquium on 29 Nov 2023 (Wed), 3pm at SPMS LT3 by our distinguished speakers, Prof Liu Xinfeng and Assoc Prof Zhang Qing.
The event is jointly organised by IAS@NTU and the Graduate Students' Clubs of EEE, MSE and SPMS.
“Ultrafast Optical Imaging: Exploring the Secrets of Semiconductor Materials” by Prof Liu Xinfeng
Ultrafast spectroscopy imaging is an important technical means for the characterisation of charge carriers, which are widely used in the fields of materials, information, physics and chemistry. In recent years, we have been committed to developing spectral measurement systems with spatial, temporal, and momentum resolution capabilities, studying the carrier characteristics in semiconductor material systems, and laying an important foundation for a deeper understanding of their photoelectric properties and related devices. In this talk, I mainly introduce some progress based on micro/nanoscale ultrafast spectroscopy imaging in the study of carrier mobility, electron phonon coupling, as well as the spectral characteristics and related carrier dynamics of nanoscale semiconductor materials induced by the edges.
Prof Liu’s research focuses on the study of high spatial and temporal resolution ultrafast dynamics and related physical and chemical properties. He served as peer reviewer for Nature Nanotechnology, Science Advances, Nature Communications, as well as editorial board member of Journal of Physics: Photonics, Frontiers of Physics, InfoMat, and Youth Editorial Board of Materials Today Physics. Prof Liu obtained his PhD from the National Nanoscience Center, and engaged in postdoctoral research at Nanyang Technological University from 2011 to 2015. Thereafter, he joined the National Center for Nanoscience and Technology of China through the Overseas Talent Program of the Chinese Academy of Sciences. In 2023, he was supported by the Outstanding Youth Program of the National Science Foundation of China.
“The Development of Micro/Nano-Lasers: Small Size, Low Energy Consumption” by Assoc Prof Zhang Qing
Lasers are coherent and strong light sources that have been broadly used in the optical communications, medical diagnosis, bio-images, and manufactures. Developing the micro/nano-sized lasers is an important topic for the development of low energy consumption and integrated photonic devices and increasing the spatial resolution of imaging and manufacture. However, the working thresholds of lasers are increased quickly with decreasing dimensions. In recent years, we are devoted to the development of low-threshold micro/nano-lasers, including the fabrication, light-matter interaction and device design of lasing materials. By using the emerging materials such as halide perovskites, MoS2, and introducing strong exciton-photon interaction, we realised the continuous-wave optically pumped lasers with device area below 1 mm2.
Assoc Prof Zhang Qing’s research is committed to the fabrication, photophysics of metal halide perovskite and two dimensional semiconductors as well as their applications in nanophotonics. She obtained her bachelor degree in materials physics from the University of Science and Technology, China and PhD in physics from Tsinghua University (with Prof Xie Qikun and Prof Jia Jinfeng). She was a postdoctoral research fellow of Nanyang Technological University from 2011 to 2016 with Prof Xiong Qihua. Thereafter, she started independent research career in Peking University as assistant professor and was promoted to tenured associate professor in 2022.