Using a tabletop laser, a University of Rochester optical scientist has turned pure aluminum, gold.
And blue. And gray. And many other colors. And it works for every metal tested, including platinum, titanium, tungsten, silver, and gold.
Chunlei Guo, the researcher who a year ago used intense laser light to alter the properties of a variety of metals to render them pitch black, has pushed the same process further in a paper in todays Applied Physics Letters. He now believes its possible to alter the properties of any metal to turn it any coloreven multi-colored iridescence like a butterflys wings.
Since the process changes the intrinsic surface properties of the metal itself and is not just a coating, the color wont fade or peel, says Guo, associate professor of optics at the Institute of Optics at the University of Rochester. He suggests the possibilities are endlessa cycle factory using a single laser to produce bicycles of different colors; etching a full-color photograph of a family into the refrigerator door; or proposing with a gold engagement ring that matches your fiances blue eyes.
Since the discovery of the black metal weve been determined to get full control on getting metals to reflect only a certain color and absorb the rest, and now we finally can make a metal reflect almost any color we wish, says Guo. When we first found the process that produced a gold color, we couldnt believe it. We worked in the lab until midnight trying to figure out what other colors we could make.
Guo and his assistant, Anatoliy Vorobeyv, use an incredibly brief but incredibly intense laser burst that changes the surface of a metal, forming nanoscale and microscale structures that selectively reflect a certain color to give the appearance of a specific color or combinations of colors.
The metal-coloring research follows up on Guos breakthrough black metal discovery in late 2006, when his research team was able to
|Contact: Jonathan Sherwood|
University of Rochester