Optical fiber point sensors based on forward Brillouin scattering.

Forward Brillouin scattering interactions support the sensing and analysis of media outside the cladding boundaries of standard fibers, where light cannot reach. Quantitative point-sensing based on this principle has yet to be reported. In this work, we report a forward Brillouin scattering point-sensor in a commercially available, off-the-shelf multi-core fiber.

Forward stimulated Brillouin scattering and opto-mechanical non-reciprocity in standard polarization maintaining fibres.

Opto-mechanical interactions in guided wave media are drawing great interest in fundamental research and applications. Forward stimulated Brillouin scattering, in particular, is widely investigated in optical fibres and photonic integrated circuits. In this work, we report a comprehensive study of forward stimulated Brillouin scattering over standard, panda-type polarization maintaining fibres.

Azimuthal and radial shaping of vortex beams generated in twisted nonlinear photonic crystals.

We experimentally demonstrate that the orbital angular momentum (OAM) of a second harmonic (SH) beam, generated within twisted nonlinear photonic crystals, depends both on the OAM of the input pump beam and on the quasi-angular momentum of the crystal. In addition, when the pump's radial index is zero, the radial index of the SH beam is equal to that of the nonlinear crystal. Furthermore, by mixing two noncollinear pump beams in this crystal, we generate, in addition to the SH beams, a new "virtual beam" having multiple values of OAM that are determined by the nonlinear process.

Twisting light by nonlinear photonic crystals.

We report the observation of nonlinear interactions in quadratic nonlinear crystals having a geometrically twisted susceptibility pattern. The quasi-angular-momentum of these crystals is imprinted on the interacting photons during the nonlinear process so that the total angular momentum is conserved. These crystals affect three basic physical quantities of the output photons: energy, translational momentum, and angular momentum.