Optical properties study on some nematic liquid crystals in the terahertz range

Because of its unique nature, terahertz radiation has wide application prospects in physics, chemistry, biomedicine, communications, radar and security checks, etc. Liquid crystal, which is a kind of macromolecule soft material with special properties in physical and chemical, has been widely used in planar displays. Recently, much attention has been paid to non-display studies of liquid crystals, covering the fields of biology, chemistry, physics, material and engineering. In this paper, the transmission spectra of several nematic liquid crystals such as 5CB, TEB300, RDP-92975 are measured by THz time-domain spectroscopy technique and free-space electro-optic sampling method. The absorption coefficients of liquid crystals in the THz range are calculated. Furthermore, the optical parameters are compared and analyzed, expecting to fill the spectrum gap of liquid crystals in the THz range and provide the experimental and theoretical foundation for the application of liquid crystals.

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