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Updated: Jan 28, 2026
Utilization of Plasmonic and Photonic Crystal Nanostructures for Enhanced Micro- and Nanoparticle Manipulation
Published on: September 27, 2011
Manipulation enhancement of terahertz liquid crystal phase shifter magnetically induced by ferromagnetic
Yunyun Ji1, Fei Fan, Shitong Xu
1Institute of Modern Optics, Nankai University, Tianjin 300350, China. fanfei@nankai.edu.cn.
Abstract:
Ferromagnetic liquid crystals (FLCs), the suspensions of magnetic nanoparticles dispersed at different concentrations in liquid crystals (LCs), and their special magnetically induced birefringence characteristics have been investigated in the terahertz regime, mainly focusing on the interaction between magnetic cluster chains and LC molecules. We experimentally demonstrated the surface anchoring effect of the magnetic cluster chains on LC molecules in a mm-thick LC cell under an extremely weak external magnetic field (EMF), leading to a uniform anchoring arrangement of the LC molecules over the entire LC cell. Unlike pure 5CB LCs, the phase shift range of the FLCs at 1.45 THz up to π (no to ne or ne to no) can be achieved over the whole tunable range by simply changing the magnitude of the EMF without changing its direction, and the optical axis of LC molecules can be controlled to rotate by 90°, thereby realizing a tunable THz wave plate. This work provides a new way in the development of THz magneto-optic devices and phase devices.
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