Discrete Terahertz Beam Steering with an Electrically Controlled Liquid Crystal Device

We present an electronic beam switching/steering device for operation at THz frequencies. The propagation direction of the THz beam is switched via electronic manipulation of the refractive index of a liquid crystal. The design of the steering device and the parameters of the liquid crystal are described and angle-dependent THz-TDS measurements of the beam steering are reported. This device is able to deflect the propagation direction of the THz beam by 6.3 °. This particular device approach offers a viable option for beam steering/switching in various THz applications including fiber switches, scanning imagers, and free-space communication systems in which the detector or emitter is in motion.

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