A joint research team led by Prof. Dai Qing and Prof. Li Chi from the National Center for Nanoscience and Technology (NCNST) of the Chinese Academy of Sciences (CAS) has demonstrated the coherent ultrafast photoemission from a single quantized energy level of a carbon nanotube. The study was published in Science Advances on Oct. 12.
Exploring dynamical processes at extreme spatiotemporal scales is pivotal for scientific and technological advancements. This is particularly true in the microscopic realm, where most movements are ultrafast, especially at the atomic spatial scale, since ultrafast processes can reach durations of a few femtoseconds or even attoseconds.
Compared with ultrafast light pulses, ultrafast electron pulses offer both high temporal and spatial resolution, making them a promising next-generation ultrafast characterization technology that could potentially exceed attosecond light pulses.
The monochromaticity of the electron source is vital for achieving high spatial resolution. However, the strong interaction between electrons and the optical field results in excited electrons occupying a wide range of energy levels. This leads to significant energy dispersion (>600meV) in ultrafast electron sources that rely on traditional metal nanostructures.
To address this issue, Prof. Dai’s team proposed the use of carbon nanotubes as ultrafast electron source materials, replacing conventional metal nanostructures in their previous study.
2023-10-16 09:00:04
Post from phys.org