Light whispers

A microscopic "whispering gallery" for light has been created by saturating molten gold with a zinc oxide plasma to create an array of tiny spires. The material carries light of different wavelengths like a whispering gallery carries sound. Visitors to the rotunda in London's St. Paul's Cathedral can hear each other's whispered conversations from one end of the gallery to the other because of the way the walls curve. Now, Marius Grundmann of the University of Leipzig in Germany and his team have fabricated and analyzed a tiny whispering gallery that has a similar effect to the rotunda but with visible light rather than sound waves. The nano-gallery is built from tiny needles of zinc oxide with a hexagonal cross section that are each just 800 nanometers long. The researchers suggest that their needles will help researchers understand the behavior of light at nanoscales, an important step in creating nanolasers for quantum data transfer, microscopy, and lithography.