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Laser ablation or photoablation (also called laser blasting [1] [2] [3]) is the process of removing material from a solid (or occasionally liquid) surface by irradiating it with a laser beam. At low laser flux, the material is heated by the absorbed laser energy and evaporates or sublimates .
Laser ablation synthesis in solution (LASiS) is a commonly used method for obtaining colloidal solution of nanoparticles in a variety of solvents. [ 1 ] [ 2 ] Nanoparticles (NPs,), are useful in chemistry, engineering and biochemistry due to their large surface-to-volume ratio that causes them to have unique physical properties. [ 3 ]
A plume ejected from a SrRuO 3 target during pulsed laser deposition. One possible configuration of a PLD deposition chamber. Pulsed laser deposition (PLD) is a physical vapor deposition (PVD) technique where a high-power pulsed laser beam is focused inside a vacuum chamber to strike a target of the material that is to be deposited.
Pulsed operation of lasers refers to any laser not classified as continuous wave, so that the optical power appears in pulses of some duration at some repetition rate. [1] This encompasses a wide range of technologies addressing a number of different motivations. Some lasers are pulsed simply because they cannot be run in continuous mode.
A flash lamp pumped Nd:YAG laser normally has a pulse duration on the order of hundreds of microseconds to a millisecond, peak power in the order of sub MW/cm 2, and material removal rate of ten to hundreds of micrometers per pulse. For machining processes by each laser, ablation and melt expulsion typically coexist. [citation needed]
Laser types with distinct laser lines are shown above the wavelength bar, while below are shown lasers that can emit in a wavelength range. The height of the lines and bars gives an indication of the maximal power/pulse energy commercially available, while the color codifies the type of laser material (see the figure description for details).
Samples spotted on a SELDI surface are typically analyzed using time-of-flight mass spectrometry. An irradiating laser ionizes peptides from crystals of the sample/matrix mixture. The matrix absorbs the energy of the laser pulse, preventing destruction of the molecule, and transfers charge to the sample molecules, forming ions.
When such a laser pulse is adsorbed by a solid target, material from the surface region of the target absorbs the laser energy and either (a) evaporates or sublimates from the surface or is (b) converted into a plasma (see laser ablation). These particles are easily transferred to the substrate where they can nucleate and grow into nanowires.