Tuesday, July 12, 2016
Abstract-Electrically tunable superconducting terahertz metamaterial with low insertion loss and high switchable ratios
With the emergence and development of artificially structured electromagnetic active terahertz (THz) devices have attracted significant attention in recent years. Tunability of transmission is desirable for many applications. For example, short-range wireless THz communications and ultrafast THz interconnects require switches and modulators. However, the tunable range of transmission amplitude of existing THz devices is not satisfactory. In this article, we experimentally demonstrate an electrically tunable superconducting nitride device and employ a hybrid coupling model to analyze its optical transmission characteristics. The maximum at 0.507 THz is 0.98 and decreases to 0.19 when the applied voltage increases to 0.9 V. A relative transmittance change of 80.6% is observed, making this device an efficient narrowband THz switch. Additionally, the frequency of the peak is red shifted from 0.507 to 0.425 THz, which means that the device can be used to select the frequency. This study offers an alternative tuning method to existing optical, thermal, magnetic-field, and electric-field tuning, delivering a promising approach for designing active and miniaturized THz devices.