We have developed a non-contact birefringence probing method for studying the dielectric heating-induced temperature rise of dual-frequency liquid crystals (DFLCs). The dielectric heating effects of three DFLC mixtures are investigated quantitatively. By properly choosing the molecular structures, the dielectric heating effect can be minimized while keeping other desirable physical properties uncompromised.
Smart liquid crystal (LC) millimeter-wave (MMW) electronic devices are demonstrated using the electrically- controllable permittivity through LC directors’ reorientation. In this paper, we review the LC classes and its important physical properties for the proposed applications. Some commercially available LCs exhibit a relatively large birefringence (Δn~0.2) in MMW bands and, therefore, are useful for millimeter wave devices. A nonradiative dielectric waveguide using LC is proposed and characterized using numerical simulations. The simulation results show that the LC waveguide is promising for future MMW technologies.