Nano-Scale Vee Yagi-UDA Antenna Based Nano Shell-Silver Coated Silica for Tunable Solid –State Laser Applications

Abstract

A numerical study on the performance of the nano-scale antenna based on VeeYagi-Uda geometry that is constructed from Nano Shell-Silver Coated Silica (NSSCS) chains is investigated for tunable solid-state laser applications. In this study, a Finite Integral Technique (FIT) based on the formulations of Computer Simulator Technology-MicroWave Studio (CST MWS) software package is invoked to evaluate the antenna parameters such as: Reflection coefficient (S11), gain/ directivity, and directivity. Before conducting the simulation study, the refractive index properties of the NSSCS are evaluated according to Lorentz distribution function of a hetero-structure junction. The proposed antenna shows three resonance modes at 75 THz, and 175 THz, and 266 THz. It is found the best antenna matching, S11<-10dB, at 75 THz and 175 THz about -23 dB and -15 dB, respectively. However, at 266 THz, it is found -3 dB in max. The antenna shows acceptable gain values at the three considered frequencies about 2.5 dBi, 3.5 dBi, and 2 dBi, consistently. Therefore, the antenna exhibits a high directivity at 175 THz and 266 THz in comparison to the first mode at 75 THz. Next, a matching circuit is coupled to a nano-circuitry to tune antenna around 175 THz. The maximum emitted electric field is found to be around 175 THz. Finally, it is found that the introduction of the matching circuit has a significant tuning ability on the second mode at 175 THz; however, at the other two modes the tuning does not show a significant change