报告题目: Studying Ultrafast Dynamics of Free Standing
Nanoparticles
报告人: Dr. Wei Xiong, JILA, University of
Colorado at Boulder, University of California, San Diego
报告时间：2014年04月15日（周二）下午15：30
报告地点：物理研究所M236会议室
邀请人及联系人：赵继民 副研究员
联系电话： 82649408
摘要：
Nanomaterials are
revolutionizing both science and technology fields, such as using various
nanoparticles assemble advanced nano-architectures. Because of the recent
advances of developing nano-devices, it becomes necessary to learn more
fundamental knowledge of these nanoparticles, such as electronic structures and
dynamics. This information can help us better control the charge flow or
generation from the nanoparticles.
In this talk, I will
present Nanoscale Velocity Map Imaging spectroscopy, a new method to
characterize the electronic structure and dynamics of nanoparticles. By forming
nanoparticle stream in the gas phase, the influences from any solvents and
substrates are minimized. Therefore, the photoelectrons of nanoparticles are
little perturbed. In addition, this new method also eliminates any sample
degrading issues, which allows us to study nanoparticle dynamics under extreme
conditions, such as nanoplasma explosion.
I
will discuss two nano systems we explored: 1) Mapping the interfacial exciton
wavefunction and ultrafast charge transfer dynamics in quantum dots, and 2)
Observing shock wave formation in a nanoplasma explosion dynamics. At the end of my talk, I will discuss the
recent advances of developing table-top attosecond X-ray light source and the
possibility to use it to explore nanoparticle dynamics.
报告人简介：
Dr. Xiong received his B.S. from Peking University
in 2006. He received his PhD degree from University of Wisconsin, Madison in
2011, under the supervision of Prof. Martin Zanni. At UW, Wei developed novel
2D IR and 2D SFG spectroscopies and applied them into different topics. During
his postdoc in the Kaptyen–Murnane group at JILA, University of Colorado at
Boulder, Wei developed table-top transient soft x-ray spectroscopy to study gas
phase dynamics and also developed photoelectron spectroscopy of nanomaterials.
Dr. Xiong will start an independent group at the department of Chemistry and
Biochemistry in UC San Diego in 2014.
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