Lateral Stress Detection Using a Tapered Fiber Mach–Zehnder Interferometer

In this letter, a novel approach to measure local lateral stress using a tapered fiber Mach–Zehnder interferometer (TFMZI) is proposed and demonstrated. The transmission spectra of the TFMZI are measured under different transverse pressures and loading positions. The responses of the TFMZI are analyzed in a spatial frequency domain by fast Fourier transform of the corresponding transmission spectra. The proposed approach allows an effective detection of lateral stress-induced fiber deformation at different positions along a TFMZI.