Electro-Optic Coefficient Measurements for ZnxCd1-x Te Single Crystals at 1550 nm Wavelength

Nonlinear optical materials of the type Zn _x Cd_1-x Te single crystals, where x = 0.0, 0.2, 0.4, 0.6, 0.7, 0.8, and 1.0, have been grown by the Bridgman method, using a vertical furnace. We have investigated the electro-optic (E-O) coefficient and refractive index of Zn _x Cd_1-x Te single crystals at optical communication wavelength (1550 nm). In the case of CdTe crystal, the E-O coefficient was 15.5 × 10^-12 m/V, which is the biggest among the E-O coefficients of Zn _x Cd_1-x Te crystals. The E-O modulation signal was very big in low frequency range (DC-100kHz), but the signal amplitude became smaller as we increased frequency above 100 kHz. We also found the acousto-optic modulation at CdTe single crystals.