A year ago, two research teams made big news by slowing the propagation of light through a vapor trap to a virtual stop. Now a group led by Philip R. Hemmer of the Air Force Research Laboratory at Edwards Air Force Base, Calif., and M. Selim Shahriar of Massachusetts Institute of Technology in Cambridge has developed a method to capture light for tenths of a second in an yttrium-silica crystal.Shahriar said the technique is expected to facilitate the application of light trapping because of its durability and additional slowing potential, and because the crystal can handle multiple pulses simultaneously. He predicted that one of the first uses will be quantum encryption.