Prof. Frank Hegmann [University of Alberta, Canada]

Title: Imaging ultrafast dynamics on the nanoscale with terahertz scanning tunneling microscopy | 用扫描隧道显微镜的太赫兹成像在纳米尺度下的超快动力学

Time: 10:00 - 11:00 AM, Wednesday, November 23, 2016

Place: Conference room 410, HPSTAR (Shanghai)

Host: Dr. Xiaojia Chen

Abstract

The ability to directly probe ultrafast phenomena on the nanoscale is essential to our understanding of excitation dynamics on surfaces and in nanomaterials. Recently, a new ultrafast STM technique that couples terahertz (THz) pulses to the scanning probe tip of an STM was demonstrated (THz-STM), providing simultaneous 0.5 ps time resolution and 2 nm spatial resolution under ambient laboratory conditions. This talk will discuss how THz-STM works and its potential for probing sub-picosecond dynamics on surfaces with atomic resolution.

Biography of the Speaker:

Frank Hegmann received his PhD in Physics from McMaster University in 1994 and then worked as a postdoctoral researcher at the Center for Terahertz Science and Technology at the University of California, Santa Barbara. In 1997, he started as an assistant professor in the Department of Physics at the University of Alberta studying ultrafast dynamics in materials using time-resolved terahertz (THz) pulse spectroscopy. He is currently a Professor in Physics and AITF Strategic Chair in Terahertz Science and Technology with research interests in THz pulse spectroscopy, ultrafast imaging, THz-STM, terahertz nonlinear dynamics, and biological effects of intense THz pulses.