کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5368206 | 1388385 | 2007 | 4 صفحه PDF | دانلود رایگان |
The formation of dense arrays of nanospikes occurs under laser ablation of bulk targets (Ag, Au, Ta, Ti) immersed in liquids such as water or ethanol. The average height of spikes is 50Â nm and their density on the target amounts to 1010Â cmâ2. The effect is observed with sufficiently short laser pulses. In particular, either a 350Â ps or a 90Â ps Nd:YAG lasers are used in their fundamental harmonics. The nanospikes are characterized by UV-Visible reflection spectrometry and atomic force microscopy. The oscillations of electrons within nanospikes result in a permanent coloration of the surface and a modification of the optical reflection spectra of the metal. Scanning the laser beam along the metal surface allows its nanostructuring over extended areas (â¼1Â cm2). The nanostructured Ag surface shows enhanced Raman scattering of acridine molecules at a concentration of 10â5Â M/l, whereas the initial Ag targets do not show any signal within the accuracy of measurements.
Journal: Applied Surface Science - Volume 254, Issue 4, 15 December 2007, Pages 1236-1239