Optical properties of LiNbO3/Au/Ti under the external electric field

Abstract

Transmittance and polarization properties of the LiNbO3 crystal are critical parameters. Here, asymmetrical Au/Ti grating is used to modulate the nonlinear properties of the LiNbO3 crystal under an external electric field. The transmission spectrum of the LiNbO3/Au/Ti is studied by the spectrometer. The polarization properties of the polarized laser beam are studied by the Thorlabs PAX5710IR3 polarimeter and the Z-scanning technique. The results show that the radius of the polarized laser beam changes from 786.0 µm to 1204 µm. The LiNbO3/Au/Ti transmittance increases from 4.92 % to 11.20 %. The transmittance of the LiNbO3/Au/Ti exhibits linearly change within a certain voltage range and at z = 0 mm position. The red shift of the wavelength of the polarized laser beam can be realized by adding an external voltage on LiNbO3/Au/Ti. The change of the Stokes parameters S1, S2, S3, and the degree of optical polarization are mainly affected by the samples’ position when the external voltages change from 0 V to 10 V.