It has been experimentally demonstrated that an optical vortex produced using the bending of the glass plate with the aid of a load distributed over a finite distance of the upper surface of an optical glass plate is nearly canonical.It has been found that the generated dislocation of the phase front deviates from a pure screw dislocation toward a mixed screw-edge dislocation by no more than ~10%.

Based on the analysis of influence of a natural optical activity on the efficiency of isotropic acousto-optic (AO) diffraction, it has been found that accounting for the optical activity and a nonzero ellipticity of optical eigenwaves in quartz crystals leads to a peak-like increase in the effective elasto-optic coefficients and the acousto-optic figure of merit.We have shown that the AO figure of merit for the type I of AO interactions increases by 54%, reaching the value 1.5810 -15 s 3 /kg.In case of AO interactions of the type II, it increases by more than three times and achieves nearly the same value.A similar situation also occurs for the types III and IV of AO interactions with the acoustic wave QT 1 .In particular, the peak value of the AO figure of merit for the type III of AO interactions increases by 19% and reaches 1.2210 -15 s 3 /kg, while the AO figure of merit for the type IV of AO interactions increases more than order of magnitude (from 9.610 -17 to 1.2210 -15 s 3 /kg).The results of our study can be useful for developing the AO devices based on crystalline quartz and minimizing their energy consumption.

We employ an enhanced version of a decomposition technique, an improved Adomian decomposition method, and confirm computationally its high accuracy for a number of dark and singular cubic-quartic optical solitons which arise from the Lakshmanan-Porsezian-Daniel equation.The overall recurrent scheme applied for the governing model is elucidated and further scrutinized with regard to the optical solitons mentioned above.The computational results are promising and reveal a remarkably high level of precision.Tables of the absolute errors and illustrating plots are provided to augment the main findings of our comparative study.