Analytic approach to study a hybrid plasmonic waveguide-fed and numerically design a nano-antenna based on the new director

Abstract

In this paper, a wideband InP-based hybrid plasmonic nano-antenna (HPNA) operating at telecommunication wavelengths has been proposed. Monolithically integrating InP-based lasers with hybrid plasmonic waveguide (HPW) as a feed line of the proposed HPNA on the same InGaAsP/InP wafer can increase the antenna efficiency. A new vertical director has been employed to have a highly directive horizontal radiation pattern. This enhancement is attributed to the efficient coupling between the radiation patterns of arm elements as well as reduced side lobes and back-lobes levels due to the achieved impedance matching. As a result, the directivity has been increased considerably, 3.6 dBi at 193.5 THz (1550 nm) and 1.1 dBi at 229 THz (1310 nm). The HPNA shows the high directivity, total efficiency and quality factor of 11.8, 97.49% and 94.57, respectively. Further, to verify the validity of confining the fundamental TM mode to a thin layer with the lower refractive index, both theoretical and numerical methods have been employed. Therefore, we have derived an analytical formula to investigate the HPW dispersion relation based on the transfer matrix theory and genetic algorithm. Moreover, due to the HPNA ability to receive an optical signal from free space and transmit it to the waveguide based on the reciprocity theorem, the HPNA performance as an optical wireless on-chip nano-link has been investigated analytically and numerically. Additionally, to obtain a high optical power signal and steering the beam angle, the antenna gain and directivity have been calculated with two different types of array structure by controlling the relative phase shift between the array elements and elements number. To validate the array design performance, a three dimensional full-wave numerical simulation and array factor theory have been exploited. The HPNA fabrication is compatible with generic foundry technology.

Plasmonics for Telecommunications Applications

“…The ability of these plasmonic structures for bending of light at-will stimulated several new trends including metasurfaces, LIDAR antenna arrays, and integration with microwave photonics for the development of faster high-performance optical-wireless communication [126][127][128][129][130].…”

Theoretical analysis of a circular hybrid plasmonic waveguide to design a hybrid plasmonic nano-antenna

“…The first step to design our proposed nano-antenna is to develop a wideband nano-antenna with low loss, low reflection, high directivity, high efficiency, and a reduced transverse size. Despite some studies to develop optical features of HPNA [20][21][22][23][24][25][26] , no study has been done about the CHPWFNA. The horn nano-antenna, flared to a larger opening, is so useful in RF region because they can make uniform phase front to enhance the directivity and gain 32 .…”

“…To excite the proposed nano-antenna a waveguide port is used, which stimulates the CHPW connected to the radiation part of the nano-antenna. Also, the eigenmode solver is utilized to calculate the exact port mode (TM 01 mode) within the low refractive index layer 25 .…”

“…Recently, hybrid plasmonic waveguide-fed nano-antennas have obtained significant attention due to their ability to convert free-propagating optical radiation into localized energy and vice versa through the reciprocity theory, in addition to focusing on controlling the distribution of the local field 20 – 26 . Various topologies for hybrid plasmonic nano-antennas (HPNAs) have been proposed based on the design of rectangular hybrid plasmonic waveguide-fed (RHPW) antennas such as patch 20 , 22 , Vivaldi 23 , bowtie 21 , horn-like 24 , V- and W-shaped 25 , 26 . To design HPNAs for optical wireless communications, the critical parameters of gain, directivity, efficiency, propagation length and impedance matching play important roles.…”

“…The proposed bowtie HPNA is capable of monolithic integration with laser and photodetector at 193.5 THz with the gain of about 9 dB in the frequency range of 180 to 220 THz 21 . In our previous work, we have introduced a new vertical director to increase the directivity of the InP-based W-shaped nano-antenna to the values of 7.96 and 10.72 dBi at the wavelengths of 1,310 and 1,550 nm, respectively 25 . Moreover, based on the coupled HPW, a V-shaped nano-antenna has been proposed, which is able to receive/transmit optical signals at three telecommunication wavelengths of 850, 1,310, and 1,550 nm with the high realized gains of 10.50, 9.39, 9.05 dB, respectively, the maximum efficiency of 98%, and ∼86% bandwidth from 150 to 390 THz 26 .…”