Analysis of dual band emission in SRR integrated terahertz photoconductive antenna

A novel approach for generating dual-band emission from terahertz (THz) photoconductive antenna (PCA) is reported for the first time, by employing Split Ring Resonator (SRR). The broad emission spectrum is split up into two narrowband emission peaks by incorporating a notch filter action of SRR. The PCA integrated with SRR is excited by a femtosecond laser source to generate terahertz radiation. A single SRR ring is introduced in the front side of the PCA and two SRR rings are etched at the back side of the PCA substrate to produce dual emission peaks at 0.1 and 0.41 THz, which is considered as an optimum scheme. The directivity and the gain of the antenna at 0.1 THz are 5.89 dBi and 4.54 dB respectively and at 0.41 THz, it is observed to be 7.47 and 4.94 dBi. Integration of PCA with Split Ring Resonator (SRR) is a novel approach to achieve dual band emissions in terahertz PCA.