University of Surrey

Test tubes in the lab Research in the ATI Dance Research

Dynamics of confined plumes during short and ultrashort pulsed laser ablation of graphite

Henley, SJ, Carey, JD, Silva, SRP, Fuge, GM, Ashfold, MNR and Anglos, D (2005) Dynamics of confined plumes during short and ultrashort pulsed laser ablation of graphite PHYSICAL REVIEW B, 72 (20), ARTN 2.


Download (600kB)


The optical emission from electronically excited C species in the ablation plume following the short (ns) and ultrashort (fs) UV pulsed laser ablation of graphite is studied. Wavelength, time and spatially resolved imaging of the plume, in background pressures of inert gases such as argon and helium, is performed. Analysis of images of optical emission from C+* ions and C-2(*) radicals, yielded estimates of the apparent velocity of emitting species, which appear to arise both from the initial ablation event and, in the presence of background gas, mainly from impact excitation. At elevated background pressures of argon (P-Ar), the formation and propagation of a shock wave is observed for ns pulses, whereas for fs pulses, the propagation of two shock waves is observed. During fs ablation, the first shock wave we associate with an initial burst of highly energetic/electronically excited ablated components, indicative of an enhanced fraction of non-thermal ejection mechanisms when compared with ns ablation. The second shock wave we associate with subsequently ejected, slower moving, material. Concurrent with the plume dynamics investigations, nanostructured amorphous carbon materials were deposited by collecting the ablated material. By varying P-Ar from 5 to 340 mTorr, the film morphology could be changed from mirror smooth, through a rough nanostructured phase and, at the highest background pressures for ns pulses, to a low density cluster-assembled material. The evident correlations between the film structure, the mean velocities of the emitting C species, and their respective dependences upon P-Ar are discussed for both pulse durations. In addition, we comment on the effect of observed initial plume dynamics on the subsequent C cluster formation in the expanding plume.

Item Type: Article
Divisions : Faculty of Engineering and Physical Sciences > Electronic Engineering > Advanced Technology Institute > Nano-Electronics Centre
Authors :
Henley, SJ
Silva, SRP
Fuge, GM
Ashfold, MNR
Anglos, D
Date : 1 November 2005
DOI : 10.1103/PhysRevB.72.205413
Uncontrolled Keywords : Science & Technology, Physical Sciences, Physics, Condensed Matter, Physics, AMORPHOUS-CARBON FILMS, DIAMOND-LIKE CARBON, THIN-FILMS, 248 NM, EMISSION, FEMTOSECOND, DEPOSITION, SPECTROSCOPY, EXPANSION, VACUUM
Related URLs :
Depositing User : Mr Adam Field
Date Deposited : 27 May 2010 14:05
Last Modified : 06 Jul 2019 05:05

Actions (login required)

View Item View Item


Downloads per month over past year

Information about this web site

© The University of Surrey, Guildford, Surrey, GU2 7XH, United Kingdom.
+44 (0)1483 300800