Lateral-pressure tuning of a coaxially embedded fiber Bragg grating in a cylindrical polymeric package is demonstrated. The polymeric coating, having very low stiffness and high Poisson's ratio, enables effective transfer of the applied radial load to the axial direction. Such a transfer enhances the tuning range and reduces birefringence. A tuning range more than 1 nm, with negligible bandpass broadening and peak splitting, could be demonstrated. A lateral pressure sensitivity of 0.3 nm/(N/mm), which is almost 7 times as high as that of bare FBG, could be obtained.
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