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A niobium laser multicharged ion source was developed using laser ablation with 10-ns, 1064-nm pulses and a laser fluence of 10–83 Jcm-2. Three distinct groups of Nb ions were detected: ultrafast, fast, and thermal. The ions were accelerated and allowed to drift in a transport line containing an electrostatic ion energy analyzer, a retarding field analyzer, and a Faraday cup. Analysis of the ion energy and charge (z) showed that each group of ions experienced different acceleration potentials during plasma expansion. Time-of-flight (TOF) signal of the thermal ions showed overlap of the signals from Nb1+ and Nb2+. For the fast ion group, z up to Nb7+ was observed and the ion acceleration potential during plasma expansion increased with z, over the charge states from Nb1+ to Nb7+. The TOF signal indicated that the ultrafast ions were composed of higher-charge ions.
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Ultrafast photoinduced energy and charge transfer: concluding remarks
The ability to characterize and control the energy and charge transfer events triggered by the photoexcitation of molecules and materials is of fundamental importance to many fields, including the sustainable capture and conversion of solar energy. This article summarizes the papers that were presented and discussed at the recent Faraday discussion meeting on ultrafast photoinduced energy and charge transfer. Ultrafast laser spectroscopy and theory were at the center of discussions on photoinduced phenomena in biological and nanoscale systems of interacting absorbers. Many of the questions that motivate this field of science have occupied scientists for many decades, as a look back to a Faraday discussion meeting that took place 60 years earlier reveals.
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- Award ID(s):
- 1800471
- PAR ID:
- 10109958
- Date Published:
- Journal Name:
- Faraday Discussions
- Volume:
- 216
- ISSN:
- 1359-6640
- Page Range / eLocation ID:
- 564 to 573
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/c9fd90030f
