Linear Electro-Optic Retardation Schemes for the Twenty Classes of Linear Electro-Optic Crystals and their Applications

Abstract

All possible linear electro-optic retardation schemes for the twenty classes of linear electro-optic crystals are synthesized in this paper under the single condition that light does not split directionally in a crystal. The result of this synthesis is tabulated in Table II. It gives the retardation and permissible polarization formulas for each class of crystals. It, therefore, may be used as a guide for designing linear electro-optic devices. As an example, a linear transverse scheme for class 4̄2m crystals (KDP, ADP) is selected from this table and verified experimentally. In this scheme, light is along (110) and electric field is along (001). This particular scheme has as advantages: no need for transparent electrodes and that the induced retardation can be increased by increasing the length-to-width ratio of the crystal. Table II depicts also the variations of retardation and permissible polarizations as the direction of light and electric field change under the above condition. This provides the reader with a foundation for synthesizing the electro-optic-polarization modulation and single-side-band-suppressed-carrier modulation (SSBSC). Again, as an example, a new scheme using cubic crystals for single-side-band and/or SSBSC modulation is proposed in this paper.