Develop TE/TM Pass Filters on double-loaded-on-ridge Structure with ITO/TiN for Upstream FTTH Optical Access Networks

In this paper, TE/TM pass filters are introduced as a dual optical multiplexer in the fiber-to-the home (FTTH) uplink transmission. The architecture is implemented at 1330 nm wavelength, with a double-loaded-on-ridge structure. In the TE pass filter, TM mode couples with plasmonic mode while TE mode is guided through the core with low losses due to the effect of the two plasmonic materials. The TM mode is directed through the heart, though, in the TM pass filter. Transparent conductive oxides (TCOs) as Indium Tin Oxide (ITO), in addition to Titanium Nitride (TiN) are proposed as plasmonic materials in optoelectronics devices. TCOs possess advantages for their transparency, functionality in the NIR region, and its low real permittivity compared to other plasmonic materials. ITO/TiN combination shows better performance than single plasmonic material on the filtration process. At 1330 nm of operating wavelength, the TE-pass filter operates with an extinction ratio of 20.62 dB and an insertion loss of 0.44 dB. Moreover, the TM pass filter performs with an extinction ratio of 20.2 dB and an insertion loss of 0.36 dB. The TE and TM pass filters have a device length of 2.5 μm and 2 μm, respectively. © 2020 Elsevier B.V.