Phase-coherent control of the molecular polar order in polymers using dual-frequency interferences between circularly polarized beams

Dual-frequency interferences using appropriate combinations of circular writing beam polarizations are demonstrated to enable full control of the molecular polar order in a polymer. A comparative theoretical and experimental analysis of the all-optical poling process in the cases of linear, cohelical, and counterhelical writing polarizations is achieved. Dynamics, efficiency, phase matching, and tensorial aspects are analyzed. Nearly perfect dipolar and octupolar ordering is achieved using conventional one-dimensional molecules. As a feature of dual-frequency holography with circular polarizations, writing beam phase retardation ΔΦ is coded into a ${\chi }^{\mathrm{}\left(2\right)\mathrm{}}$ pattern rotation by the same angle. Interestingly, in the case of a fundamental beam with linear polarization, second harmonic generation is independent of the polarization direction.