Past Event · Public Lecture

Clocking Electrons: an Attosecond Stopwatch

Presented by Siqi Li

Register here to watch in person in the Kavli Auditorium, or watch the lecture live on our YouTube page.

Electrons in a molecule zip around the atom in times measured in billionths of a billionth of a second, or attoseconds. To learn the basic mechanisms of chemical reactions – how catalysts work, how batteries operate – we need to follow electrons over these very short times, and for that, we need a stopwatch that ticks in attoseconds. In this lecture, I will explain how we use SLAC's X-ray laser, the Linac Coherent Light Source (LCLS), to measure times in attoseconds. Part of the challenge is to verify that the stopwatch is accurate. This work provides tools to watch electrons move on their natural time scales.

About Siqi Li

Siqi Li is a staff scientist at SLAC in the group responsible for operating our X-ray free-electron laser, LCLS. After receiving her bachelor's degree at the University of Chicago, she came to SLAC and Stanford for graduate study, leading to her PhD in 2019.  Her thesis on the production and measurement of attosecond X-ray beams won the 2020 award for the Outstanding Doctoral Thesis in Beam Physics given by the American Physical Society. After graduating, Li joined the SLAC staff, where she continues to improve the technology that enables ultrafast science.

Past Event · Public Lecture

Clocking Electrons: an Attosecond Stopwatch

Presented by Siqi Li

Public Lectures
Public Lecture Siqi Li Poster
Thursday, September 21, 2023
7:00–8:00 p.m. PDT
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