Thermal Lens Astigmatism Induced by the Photoelastic Effect in m3m, 432, and 43m Symmetry Cubic Crystals

The expressions for the thermal lens of linearly polarized radiation arising in m3m, 432 and 4̅3m cubic crystals with arbitrary crystallographic axes orientation in the presence of circular birefringence δc are analyzed. It is shown that the thermal lens may have astigmatism the magnitude of which is proportional to the power of heat generation. The Euler angles determining the crystallographic axes orientation [P1 are found and the conditions for the material constant - optical anisotropy parameter ξ - under which the thermal lens astigmatism in active and magneto-active optical elements can be eliminated, are formulated. It is demonstrated that the orientation [P1 depends only on optical anisotropy parameter ξ of the crystal and on circular birefringence δ
_c
.