Reconfigurable and tunable terahertz wrench-shape metamaterial performing programmable characteristic.

A design of a tunable terahertz (THz) programmable device by using wrench-shape metamaterial (WSM) is presented, which is composed of a Au layer fabricated on a Si substrate. The size of the WSM unit cell is 30 µm×30 µm, and the distance between each WSM is 20 µm. The electromagnetic response of the THz programmable device exhibits the switch function for single-band resonance and dual-band resonance at the transverse electric mode and transverse magnetic mode. The resonance spans from 3.00 to 8.00 THz and is insensitive to the angle of the incident THz wave. While changing the incident angle of the THz wave, the bandwidth of the resonance becomes broader and the transmission spectrum decreases gradually. By configuring the unit cell from single-atom to quad-atom, WSM exhibits optical-logic behaviors with programmable characteristics and anti-interference. Such results are very suitable for use for an ultra-narrowband filter, single-/dual-band switch, polarization switch, and programmable device. It could potentially provide all-optical logical devices with multichannel data processing at higher bit rates.