Optical Properties of LiGdF₄ Single Crystal in the Terahertz and Infrared Ranges

Abstract

The basic mechanisms of absorption of THz range radiation in optically perfect LiGdF4 single crystals were studied using the broadband experimental data and the dielectric response function analysis within the harmonic oscillator model. The polarized IR reflection spectra have allowed one to determine the phonon contribution in the absorption coefficient in the THz range, while transmission spectra in the THz range were used to obtain the birefringence value and the effects of various mulitparticle processes. Additionally, we established the optical and electrodynamic parameters of the LiGdF4 single crystal, which are necessary for the design of nonlinear optical devices.

Keywords

• fluoride single crystals
• terahertz and infrared spectroscopy
• phonon and multiparticle absorption
• dielectric response function