Strain-sensitive elastic scattering from cylinders.

Morphology-dependent resonance features are observed in the elastic-scattering spectra of 125-μm-diameter cylinders (optical fibers) as a function of wavelength. The positions of the resonances are strain sensitive and can be tuned in a controlled manner by the application of strain with a piezoelectric transducer. The measured wavelength shifts yield a linear slope of 0.14 nm/mstrain, in good agreement with calculated shifts based on published data for the elastic moduli and the strain-optic coefficients for fused quartz. This demonstrates a new miniature optical strain-sensor technique capable of microstrain sensitivity at a single point.