Want some color with that bling? It’s now possible with SCIENCE. Nano-science.
If you want something really tacky looking, you can already get gold that has a tint to it, but it’s just tinted with some cheap, temporary process. If you really want to change the color of something permanently, you have to do so at the molecular level so that it reflects different wavelengths of visible light. And you have to do it with LASERS.
The idea is simple: rather than coating metals – especially naturally colored ones like gold and copper – with paint, these folks alter their color by using an ion beam to carve fine patterns that are smaller than visible light’s wavelength. The resultant metamaterial dramatically boosts the metals’ light absorption efficiency, thus reflecting a different color depending on the pattern’s radius and etch depth. So for instance, gold can reflect colors ranging from orange to red to green to brown with its ring pattern etch depth ranging from 85nm to 205nm, respectively.
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