Abstract
We report the first experiments carried out on a new imaging setup, which combines the high spatial resolution of a photoemission electron microscope (PEEM) with the temporal resolution of extreme ultraviolet (XUV) attosecond pulse trains. The very short pulses were provided by high-harmonic generation and used to illuminate lithographic structures and Au nanoparticles, which, in turn, were imaged with a PEEM resolving features below 300 nm. We argue that the spatial resolution is limited by the lack of electron energy filtering in this particular demonstration experiment. Problems with extensive space charge effects, which can occur due to the low probe pulse repetition rate and extremely short duration, are solved by reducing peak intensity while maintaining a sufficient average intensity to allow imaging. Finally, a powerful femtosecond infrared (IR) beam was combined with the XUV beam in a pump-probe setup where delays could be varied from subfemtoseconds to picoseconds. The IR pump beam could induce multiphoton electron emission in resonant features on the surface. The interaction between the electrons emitted by the pump and probe pulses could be observed.
| Original language | English |
|---|---|
| Article number | 123703 |
| Journal | Review of Scientific Instruments |
| Volume | 80 |
| Issue number | 12 |
| DOIs | |
| Publication status | Published - 2009 |
| Externally published | Yes |
| MoE publication type | A1 Journal article-refereed |
Funding
This work was performed within the Lund Laser Center and the Nanometer Structure Consortium at Lund University and was supported by the Swedish Research Council (VR), the Swedish Foundation for Strategic Research (SSF), the Marie Curie Early Training Site MAXLAS, the Marie Curie Intra European Fellowship Attoco, the European Research Council (project ALMA), the Crafoord Foundation, and the Knut and Alice Wallenberg Foundation.