Nature Photonics publication : Sensitive vectorial optomechanical footprint of light in soft condensed matter

Among the properties of light that dictate its mechanical effects, polarization has held a special place since the mechanical identification of the photon spin. Nowadays, little surprise might be expected from the mechanical action of linearly polarized weakly focused (paraxial) beams on transparent and homogeneous dielectrics. Still, here we unveil vectorial optomechanical effects mediated by the material anisotropy and the longitudinal field component inherent to real-world beams. Experimentally, this is demonstrated by using an elastic anisotropic medium prone to exhibit a sensitive and reversible effect, that is, a nematic liquid crystal, and our results are generalized to vector beams. This represents an alternative to irreversible damaging approaches restricted to strongly non-paraxial fields. The reported creation of multiple self-induced lenses from a single beam also open up topology assisted all-optical information routing strategies. Moreover, our findings point out the transverse internal optical energy flows (spin and orbital) as novel triggers to tailor structured optical nonlinearities.