Proposal of an electrically controlled terahertz switch based on liquid-crystal-filled dual-metallic grating structures

We propose an electrically controlled terahertz switch based on metallic grating-liquid crystal-metallic grating (MG-LC-MG) structures. The switching mechanism is realized by modifying the effective refractive of the LC using different bias electric fields. In our design, the MGs not only support supertransmittance at certain frequencies, but they also act as the electrodes. Simulation results show the proposed structure has the potential to realize an electrically controlled terahertz switch with a high extinction ratio and low insertion loss. A prototype design is also proposed for practical implementation. (C) 2010 Optical Society of America