Dissipation of mechanical energy in fused silica fibers

To determine the dissipation induced by the surface of fused silica fibers, we measured the quality factor of fibers having various diameters. We meas ured a maximum quality factor of 21 million and extrapolated to obtain an i ntrinsic quality factor for fused silica of 30 million. Dissipation in the surface dominated at diameters less than about 1 mm. We developed a method for characterizing surface-induced dissipation that is independent of sampl e geometry or mode shape. (C) 1999 American Institute of Physics. [S0034- 6 748(99)01610-X].