Highly Directive Hybrid Plasmonic Leaky-Wave Optical Antenna With Controlled Side-Lobe Level

Abstract

Various configurations are proposed to engineer the pattern of optical leaky-wave antennas with the goal of achieving a desired side-lobe level (SLL). By the aid of the proposed algorithm, two types of hybrid plasmonic optical traveling wave antennas with controlled SLL are designed and numerically analyzed. The antennas are designed to operate at the standard telecommunication wavelength of 1550 nm, and have a wide bandwidth that completely cover the standard optical communication bands of E, S, and C. The first configuration in which the tapering is applied to the width of slots results in a broad bandwidth of 28 THz, a high directivity of 14.6 dBi, an efficiency of 73%, and a low SLL of $-$ 19.4 dB. The second configuration, in which wall tapering is applied, exhibits a bandwidth greater than 30 THz, a high directivity of 13.6 dBi, an efficiency of 79%, and an excellent SLL of $-$ 25 dB. Thanks to the high gain and low SLL, these devices can have applications in integrated optical interconnects, highly integrated optical beam-steering devices, such as active LIDARs and solar cells with high efficiency.