Study of Human Lymph Nodes using Terahertz Imaging

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Quantitative Analysis for THz Scanning Near-Field Microscopy based on Line Dipole Image Method

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Terahertz properties of liquid crystals

Liquid crystals (LCs) represent a very interesting material in the visible range but their properties in the terahertz (THz) range have not been extensively investigated yet. In this paper, we have investigated the THz properties of a set of LCs E7, BL037, and RDP97304 using terahertz time-domain spectroscopy. Refractive indices and absorption coefficients of ordinary and extraordinary axis of LCs are extracted from the measurements. We find that RDP97304 has the largest birefringence and smallest absorption in the THz range compared to E7 and BL037. Thus, RDP97304 is useful for developing efficient and fast THz devices

Micrometer Scale Resolution Limit of a Fiber-Coupled Electro-Optic Probe

We present the practical resolution limit of a fine electrical structure based on a fiber-coupled electro-optic probing system. The spatial resolution limit was experimentally evaluated on the sub-millimeter to micrometer scale of planar electrical transmission lines. The electrical lines were fabricated to have various potential differences depending on the dimensions and geometry. The electric field between the lines was measured through an electro-optic probe, which was miniaturized up to the optical bare fiber scale so as to investigate the spatial limit of electrical signals with minimal invasiveness. The experimental results show that the technical resolution limitation of a fiber-coupled probe can reasonably approach a fraction of the mode field diameter (~10 μm) of the fiber in use

Evaluating liquid crystal properties for use in terahertz devices

Despite the wide application of liquid crystals (LCs) in the visible frequency range, their properties in the terahertz range have not yet been extensively investigated. In this paper we have investigated the terahertz properties of LCs E7, BL037, RDP-94990 and RDP-97304 using terahertz time-domain-spectroscopy. We find that RDP-94990 has the largest birefringence and smallest absorption in the terahertz range compared to E7 and BL037. We highlight the importance of investigating all parameters, not just the birefringence, when designing fast, efficient and transmissive terahertz LC devices. (c) 2012 Optical Society of Americ