| Popis: |
We report measurements of proton‐exchanged LiNbO3 using acoustic microscopy in the V(z) mode, together with optical waveguide mode observations. In the present case, samples were prepared using dilute benzoic acid containing a small mole percent of lithium benzoate. Substantial changes in surface acoustic wave (SAW) propagation velocity due to proton exchange have been observed on all three major‐axis crystal cuts, with both increase and decrease in velocity occurring, depending on propagation direction. Changes in attenuation are also observed. Using the V(z) technique with a line‐focus cylindrical lens has enabled complete velocity surfaces for proton‐exchanged lithium niobate to be obtained with reasonable precision, based on simplified isotropic calculations of acoustic propagation in layered media and the assumption that the proton‐exchange region is uniform with a depth obtainable from optical waveguide mode calculations. It is concluded that the V(z) acoustic microscopy technique can provide a powe... |
