Strength of silica optical fibers with micron size flaws

Silica fibers have been indented with a diamond having a cube-corner tip. The tensile strengths of fibers indented with loads from 0.2 to 10 g were 465–130 MPa, respectively, with Weibull m-values ∼30–70. Radial cracks (0.5–6.5 μm) were produced in all cases, with no transition to sub-threshold behavior at the lowest load (0.2 g) employed.