Maple-Leaf Shaped Broadband Optical Nano-Antenna with Hybrid Plasmonic Feed for Nano-Photonic Applications  
[PERSON]  
1 Department of Telecommunication Engineering, University of Engineering and Technology,  
Mardan 23200, KP, Pakistan; [EMAIL_ADDRESS] (I.A.) [EMAIL_ADDRESS] (S.U. ); [EMAIL_ADDRESS] (W.U. )1  
[PERSON]  
1 Department of Telecommunication Engineering, University of Engineering and Technology,  
Mardan 23200, KP, Pakistan; [EMAIL_ADDRESS] (I.A.) [EMAIL_ADDRESS] (S.U. ); [EMAIL_ADDRESS] (W.U. )1  
[PERSON]  
2 Department of Electrical Engineering, University of Engineering and Technology,  
Peshawar 25120, KP, Pakistan; [EMAIL_ADDRESS] (W.U. )2  
[PERSON]  
1 Department of Telecommunication Engineering, University of Engineering and Technology,  
Mardan 23200, KP, Pakistan; [EMAIL_ADDRESS] (I.A.) [EMAIL_ADDRESS] (S.U. ); [EMAIL_ADDRESS] (W.U. )2  
[PERSON]  
1 Department of Telecommunication Engineering, University of Engineering and Technology,  
Mardan 23200, KP, Pakistan; [EMAIL_ADDRESS] (I.A.) [EMAIL_ADDRESS] (S.U. ); [EMAIL_ADDRESS] (W.U. )2  
[PERSON]  
3 School of Computer Science and Electronic Engineering, Bangor University, Bangor LL57 2 DG, UK 3  
[PERSON]  
4 College of Engineering, King Saud University, P.O. Box 800, Riyadh 11421, Saudi Arabia; [EMAIL_ADDRESS]. by [10] to design a Spiral shell shaped antenna for the multi-band frequency operation. Additionally, it is extended to a dielectric resonator based prototype design in [11]. The optical antenna is a practicable application of physical optics that has the capability of capturing and converting free propagating optical electromagnetic radiation to localized energy and vice versa [12]. These antennas resemble the typical microwave counterparts as they deal with optical fields to confine, transmit, and receive. By making use of the localized surface plasmons (LSP), these antennas can restrain optical (light) waves into very small volumes [13]. The basic principle for that is the induction of free elections by the metal particles due to the illumination of light. These electrons oscillate as a result and, in turn, generate surface charges which change corresponding to the incident light. The aggregations of surface charges that happen on opposite sides of the particles are called surface plasmons (SPs) and they are actually coherent electron oscillations that arise when there is an interface between metal and dielectric [14]. Although optical antennas are strongly analogous to their radio-frequency (RF) and microwave counterparts, their physical properties and scalable behaviors are much different. Most of these differences arise due to the fact that metals are not perfect conductors [15] at optical frequencies. However, they are strongly correlated plasmas, and thus can be described as a free electron gas that can be defined and solved using Drude model equations [16]. For these reasons, modern advancements in nanotechnology and plasmonic technology have generated substantial interest in the optical antenna concept to efficiently overcome the diffraction limit and make it possible to manipulate optical fields on a nanometer scale [17]. The optical nano-antennas can impressively increase the light-matter interaction efficiency, to get a wide range of applications, such as chemical and biological sensing [18], high-resolution microscopy [19], and nanoscale imaging [20]. Additionally, nano-antennas have been considered as efficient and promising elements in photo-detection [21], heat-transfer (thermal ablation of liver and cancer cell) [22], inter-and/or intra-chip optical communications or radio-over-fiber transmission [23], spectroscopy [24], and energy harvesting [25,26]. Several different nano-antenna configurations have been demonstrated so far, such as bow-ties [27], Yagi-Uda [28], cross antennas [29], half-moon shape antenna [30], Crescents [31], and Nanorods [32]. Most of them are with limited bandwidth due to their dipolar type of resonances. Therefore, these configurations are only suitable for narrowband applications.