Acousto-optic modulation of a 1 cm fiber Bragg grating at 10.9 MHz frequency and 1065 nm wavelength is demonstrated for the first time. A special modulator design is employed to acoustically induce a dynamic radial long period grating which couples power of the fundamental mode to the higher-order modes supported by the Bragg grating. A modulated reflection band with a depth of 16 dB and 320 pm bandwidth has been achieved. The results indicate a higher modulation frequency compared to previous studies using flexural acoustic waves. In addition, the reduction of the grating length and the modulator size points to compact and faster acousto-optic modulators.
Silva, R. E., Tiess, T., Becker, M., Eschrich, T., Rothhardt, M., Jäger, M., Pohl, A. A. P., & Bartelt, H. (2015). All-fiber 10 MHz acousto-optic modulator of a fiber Bragg grating at 1060 nm wavelength. Optics Express, 23(20), 25972-25978. https://doi.org/10.1364/OE.23.025972