Femtosecond laser ablation

The crater surfaces obtained in the LA-TOF-MS experiment on the TiN-TiAlN-Fe sample were remarkably smooth and clearly demonstrated the Gaussian intensity distribution of the laser beam. Fig. 4.45 shows an SEM image of the crater after 100 laser pulses (fluence 0.35 J cm ). The crater is symmetrical and bell-shaped. There is no significant distortion of the single layers. Fig. 4.45 is an excellent demonstration of the potential of femtosecond laser ablation, if the laser beam had a flat-top, rather than Gaussian, intensity profile. 

The last problem of this series concerns femtosecond laser ablation from gold nanoparticles [87]. In this process, solid material transforms into a volatile phase initiated by rapid deposition of energy. This ablation is nonthermal in nature. Material ejection is induced by the enhancement of the electric field close to the curved nanoparticle surface. This ablation is achievable for laser excitation powers far below the onset of general catastrophic material deterioration, such as plasma formation or laser-induced explosive boiling. Anisotropy in the ablation pattern was observed. It coincides with a reduction of the surface barrier from water vaporization and particle melting. This effect limits any high-power manipulation of nanostructured surfaces such as surface-enhanced Raman measurements or plasmonics with femtosecond pulses. 

Silicon isotope ratios have been generally measured by fluorination (Douthitt 1982 Ding et al. 1996). However, the method is time consuming and potentially hazardous, therefore, more recently MC-ICP-MS techniques have been introduced (Cardinal et al. 2003 Engstrom et al. 2006). Determinations with SIMS have been carried out by Robert and Chaussidon (2006). Very recently, Chmeleff et al. (2008) have shown that a UV-femtosecond laser ablation system coupled with MC-ICP-MS gives S Si and 5 °Si-values with very high precision. 

Chivas AR, Andrew AS, Sinha AK, O Neil JR (1982) Geochemistry of Phocene-Pleistocene oceanic arc plutonic complex, Guadalcanal. Nature 300 139-143 Chmeleff J, Horn 1, Steinhofel G, von Blanckenburg L (2008) In situ determination of predse stable Si isotope ratios by UV-femtosecond laser ablation high-resolution multi-coUector ICP-MS. Chem Geol 249 155-160... 

The last problem of this series concerns femtosecond laser ablation from gold nanoparticles [87]. In this process, solid material transforms into a volatile phase initiated by rapid deposition of energy. This ablation is nonthermal in nature. Material ejection is induced by the enhancement of the electric field... 

Femtosecond Laser Ablation and Generated Impulsive Force in Water LaserTsunami... 

Hosokawa, Y., Yashiro, M., Asahi, T., Fukumura, H. and Masuhara, H. (2000) Femtosecond laser ablation dynamics of amorphous film of a substituted Cu-phthalocyanine. Appl. Surf. Sci., 154-155, 192-195. 

Chinese gold with femtosecond laser ablation-inductively coupled mass spectrometry. Journal of Archaeological Science 36(2) 461-466. 

Horn, I., von Blanckenburg, F., Schoenberg, R., StEINHOEFEL, G. MaRKL, G. 2006. In-situ iron isotope ratio determination using UV-femtosecond laser ablation with application to hydrothermal ore formation processes. Geochimica et Cosmochimica Acta, 70, 3677-3688. 

Koch, I, Gunther, D. (2007) Femtosecond laser ablation inductively coupled plasma mass spectrometry achievements and remaining problems. Analytical and Bioanalytical Chemistry, 387,149-153. 

Brostoff, L., Gonzalez, L, Jett, R, Russo, R. (2009) Trace element fingerprinting of ancient Chinese gold with femtosecond laser ablation-inductively coupled mass spectrometry. Journal of Archaeological Science, 36, 461 66. 

Peschel, B.U., Herdering, W., Broekaert, J.A.C. (2007) Visualization of aerosol particles generated by near infrared nano-and femtosecond laser ablation. Spectrochim. Acta Part B, 62,109-115. 

Mahmood AS, Sivakumar M, Venkatakrishnan K, Tan B (2009) Enhancement in optical absorption of silicon fibrous nanostructure produced using femtosecond laser ablation. Appl Phys Lett 95 034107... 

Hergemoder, R., Samek, O., and Hommes, V. (2006) Femtosecond laser ablation elemental mass spectrometry. Mass Spectrom. Rev., 25, 551-572. 

Koch, )., Walle, M., Pisonero,)., and Gunther, D. (2006) Performance characteristics of ultra-violet femtosecond laser ablation inductively coupled plasma mass spectrometry at -265 and -200 nm. J. Anal. At. 

Hirata, T. and Kon, Y. (2008) Evaluation of the analytical capability of NIR femtosecond laser ablation-inductively coupled plasma mass spectrometry. 

Investigation on elemental and isotopic fractionation during 196 nm femtosecond laser ablation multiple collector inductively coupled plasma mass spectrometry. Spectrochim. Acta B, 62, 410-422. 

Freydier, R., Candaudap, F., Poitiasson, F., Arbouet, A., Chatel, B., and Dupre, B. (2008) Evaluation of infrared femtosecond laser ablation for the analysis of geomaterials by ICP-MS. 

Gomez D, Goenaga I, Lizuian I, Ozaita M (2005) Femtosecond laser ablation for microfluidics. Opt Eng 44 1-8... 

Laser Ablation, Figure 1 (a) Nanosecond-pulse laser ablation of a hole In a 100 mm thick steel loll with a pulse width of 3.3 ns, fluence of 4.2 J/cm at a laser wavelength of 780 nm. (b) Femtosecond laser ablation of a hole in a 100 mm thick steel foil with a pulse width of 200 fe, fluence of 0.5 J/cm at a laser wavelength of 780 nm... 

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