Scientists Precisely Control Gold-Coated Nanoparticles with Lasers

Undeniably humans will quite soon be considered as nano-particles making them the very first life-size nanotechnology, which has been built from the scratch. Now human seems to be looking forward to return a favour pertaining to this aspect by developing a nano-scale machinery from top to down. Even though the technological world is still waiting for this dream to become a reality, looks like a less glamorous micro and nano particle technology seems to be stealing all the limelight. Although there are many kinds of particles that are used for creating finely separated spheres and powders, gold has become come out as winner in terms of being the premier element mainly due to its properties related to opto-electronics.

Reports suggest that researchers from Munich have been able to use this, currently named as ‘plasmonic gold’ to create what they claimed to be is a micro-scale photonic elevator. They stated that a lot of experiments can be done by hitting out flecks of gold through various rays of energy. These beams of energy include fluorescence, precision thermal control, and movements in 2D plane however the researchers also added that this photonic elevator is however in control of their third axis.

The Plasmon: 

An oscillation of free electrons has been termed as the Plasmon. The electron density inside the electromagnetic radiation of wavelengths can couple with the plasmonic nano-particles making it larger than the particle itself. Researchers have been trying to find out as to what differentiates these particles created by the Plasmon over the surface of any interface unique in terms of their absorbance as well as scattering properties. The Plasmon derives these properties from their shape and sizes. In simple terms, the interaction of the Plasmon with the different radiation as well light is not only dependent on their elements but they are also affected by the geometry as well as the relative positioning of other particles inside them.

Lasertrap is one such device which has been able to capture the essence of the nano-particles technology. Using this device along with different kinds of microscope will allow anyone to feel the nano. The researcher created the so called magic by coating the half of the silica beads with a thermally collected gold vapour. They stated that due to this asymmetric gold coating, the Plasmon started showcasing scattering effects by orienting the particles inside the axis of the laser light. Using the gold coating has allowed the researchers to use the benefits of opto-genetics, without the need of any real genetics.

This is the kind of technology which is being anticipated by the scientists of the National Brain initiative to research the entire brain. The gold coating and its associated effects can be highly beneficial for conducting local calibrations and to collect feedback. Emergence of these electromagnetic technologies means using the same hardware with minimum changes and getting the best possible stimulation, images, therapeutic treatments. At the end, any equipment enabled with this technology will be the dream of any neuronaut.

Laser Marking: How Do They Work

While laser engraving has a wide spectrum of uses, the more sophisticated of these is most evident in its use with specialized materials, such as polymers and alloys.  Laser marking designates a range of marking, such as printing, branding, and bonding.  The terms “laser engraving” and “laser marking” are often used interchangeably, because the equipment they use consists of the same components: laser, controller, and surface.  By movement of the laser beam, much as you would a pencil, the controller directs and controls the direction, intensity, speed and swath of the laser’s beam as it’s applied to a surface.

Laser engraving technology has been widely adopted on production lines.  It is particularly useful for high-detail relief work, such as expiration and printing dates, and lot or serial numbers.  Depending on the detail and precision involved, either a laser table (or “X-Y table”) or flat table will be used to stabilize and focus the laser beam.  Focusing systems, such as dynamic auto focus, can adjust laser parameters while an area is being engraved or marked.  Vector engraving affords a greater degree of flexibility, e.g., fill areas, font rotation, and dynamic scaling, than earlier versions of laser printing.

Raster engraving – a process in which a laser is traced across a surface, back and forth, has the advantage of virtually effortless “fill”.  When an image has large or engraved areas or bold letters, it is usually well-rasterized.   Even photos can be rasterized.

Some of the materials that can be engraved include the following:

• Wood – which is burned (literally) with images (walnut, mahogany and maple, are very suitable)
• Hard papers and fiberboard
• Some latex rubber compounds
• Plastics - acrylic plastic, acrylic plastic sheet, Bakelite, and other cast resins, all work well (additionally, silicate or other mater infused plastics are also suitable)
• Metals
• Stone and glass (specifically sandblasting or cutting with diamonds, work better with these materials)
• Jewelry
• Fine Art
  
  

Source: http://en.wikipedia.org/wiki/Laser_engraving

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Mark Williams is the author of this blog post about laser marking. He is an engineer and science geek who loves laser technology. Feel free to connect with him over at Google+.