Generation of doubly charged vortex beam by concentrated loading of glass disks along their diameter

Abstract

We show that a system of glass disks compressed along their diameters enables one to induce a doubly charged vortex beam in the emergent light when the incident light is circularly polarized. Using such a disk system, one can control the efficiency of conversion of the spin angular momentum to the orbital angular momentum by a loading force. The consideration presented here can be extended for the case of crystalline materials with high optical damage thresholds in order to induce high-power vortex beams.

Conditions of appearance of the topological defects of optical indicatrix orientation in the glasses with residual stresses: Movement of the defects under application of external mechanical stress to CaB4O7 glasses

“…We have also found that superposition of the both electrooptic effects can result in the topological reactions of birth, adding and annihilation of the TDs [9][10][11]. According to our experimental data [12][13][14][15], the mechanical stresses of bending or torsion can also induce the TDs with the half-integer strength in many situations. In particular, the TDs of OI orientation with the strength module |1/2| appear in the amorphous glass media with residual stresses [16].…”

Efficient materials for spin-to-orbit angular momentum conversion using bending technique

“…Recently we have shown that optical vortices can also be generated with the aid of parametric optical effects (e.g., piezooptic or Pockels ones) induced by inhomogeneous external fields [9][10][11][12]. For example, optical polarization singularities are successfully created using torsion of crystals, their bending [9][10][11], or loading of transparent crystalline disks compressed along their diameters [12].…”

“…For example, optical polarization singularities are successfully created using torsion of crystals, their bending [9][10][11], or loading of transparent crystalline disks compressed along their diameters [12]. It has also been found that optical polarization singularities are imposed by structural dislocations existing in crystals or by residual stresses available in glass materials [13].…”

Appearance of optical singularities at the light propagation through glasses with residual stresses

“…We remind in this respect that 2D distributions of external fields usually induce optical singularities, which appear when the incident nearly plane-wave optical beams propagate through crystalline samples (see [10][11][12][13][14][15]). The optical vortices can be induced by the mechanical stresses appearing under torsion [11,12] or bending [13,15] of crystalline samples, or under compression of disks made of optical material along their diameters [14].…”

“…The optical vortices can be induced by the mechanical stresses appearing under torsion [11,12] or bending [13,15] of crystalline samples, or under compression of disks made of optical material along their diameters [14]. Notice that all of the stressed states mentioned above correspond to 2D stress distributions.…”