Product authentication at your fingertips: Research brings rapid and reversible switching of plasmonic color to solids

Chemists have fabricated for the first time plasmonic color-switchable films of silver nanoparticles. Until now, such color changing of nanoparticles was mainly achieved in liquids, limiting their potential for practical applications. The technology has a number of applications: product authentication, color displays, signage, sensors, and information encryption.