||Atomic cluster is a unique combination of gas and solid phase components. It is normally produced inside a high-pressure gas jet that the atoms are combined through van der Waal’s force. Their solid-like local density and gas-like average density cause individual nanometer clusters efficiently to absorb laser energy, forming highly-charged hot nanoplasmas; to eject keV electrons and MeV ions, and to emit strongly from extreme-ultraviolet to x-ray. It is also demonstrated that cluster jet can be served as the gain medium of the inner-shell hard x-ray laser.|
In the past studies of the high-harmonic generation from laser irradiated clusters, it has been proved that laser induced cluster vibration will effect the efficiency of high-harmonic generation. In order to understand and control laser-cluster interaction, we develop an experimental station for pump-probe experiment with IR and x-ray pulses. We use an infrared laser pulse (λ= 810 nm) to induce cluster vibration. After a time delay , we use a soft x-ray pulse (λ= 32.8 nm) to probe the vibration. The absorption of x-ray pulses is measured. We want to find the relationship between cluster vibration and x-ray absorption by observe the variation of x-ray absorption with time delay. As a result of that cluster vibration affects the distance between atoms, understand and control of the vibration may lead us to achieve the efficient inner-shell x-ray lasing from laser irradiated clusters.
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