Recently, a team of researchers at Containerless Research Inc. in Evanston, Ill., explored using yttria and alumina compositions to expand the range of fiber lasers in the mid-IR. There was only one problem: Molten oxides that do not contain silica typically have a viscosity that is too low to allow fiber pulling. The research team used a continuous flow of inert gas to levitate the molten yttrium aluminum garnet (YAG:Y3Al5O12) to reach a level of viscosity suitable for pulling. The researchers say this method of reaching higher viscosity could lead to a number of new oxide compositions suitable for fiber.