Brillouin light scattering under one-dimensional confinement: Symmetry and interference self-canceling

We present the spontaneous Brillouin light scattering (BLS) under simultaneous one-dimensional confinement of sound and light and show that the photon-phonon coupling results from nontrivial interplay of the photoelastic and moving-interface effects. We reveal two types of BLS self-canceling: governed by mode symmetry and driven by destructive interference of the two effects. We show that the latter can be adjusted by the light polarization and phonon wave number. Furthermore, we present a measurement of the shear-horizontal waves in thin membranes.