| Autor: |
Jikun Chen, Lunney, James G., Lippert, Thomas, Ojeda-G-P, Alejandro, Stender, Dieter, Schneider, Christof W., Wokaun, Alexander |
| Předmět: |
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| Zdroj: |
Journal of Applied Physics; 2014, Vol. 116 Issue 7, p073303-1-073303-8, 8p, 1 Diagram, 8 Graphs |
| Abstrakt: |
The plasma formed in vacuum by UV nanosecond laser ablation of La0.4Ca0.6MnO3 in the fluence range of 0.8 to 1.9 J cm -2 using both Langmuir probe analysis and energy-resolved mass spectrometry has been studied. Mass spectrometry shows that the main positive ion species are Ca+ , Mn+ , La+, and LaO+. The Ca+ and Mn+energy distributions are quite broad and lie in the 0-100 eV region, with the average energies increasing with laser fluence. In contrast, the La+and LaO+distributions are strongly peaked around 10 eV. The net time-of-arrival signal derived from the measured positive ion energy distributions is broadly consistent with the positive ion signal measured by the Langmuir probe. We also detected a significant number of O- ions with energies in the range of 0 to 10 eV. The Langmuir probe was also used to measure the temporal variation of the electron density and temperature at 6 cm from the ablation target. In the period when O-ions are found at this position, the plasma conditions are consistent with those required for significant negative oxygen ion formation, as revealed by studies on radio frequency excited oxygen plasma. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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