Recently, indium tin oxide has been very attractive for thermo-optic (TO)-controlled silicon photonic devices, due to its high transparency, strong TO phase dependency, high conductivity, and CMOS compatibility. These properties enable the reduction of the gap between the silicon core and the heater, leading to a considerably low electric power consumption and high switching speed. We present an investigation of a numerical simulation to design and optimize a compact ITO microheater for tuning the TO phase shift in a proof-of-concept of a three-mode converter (TMC) with broadband and ultralow loss properties. We show that the TMC can operate the 3-dB bandwidth up to 100 nm. In addition, the designed device can attain relatively large fabrication tolerances for width and height of ±50 and ±5 nm, respectively. In addition, the proposed mode converter consumes a total power of less than 90 mW and obtains a fast switching time of less than 8 μs. Moreover, the device can be integrated into an estimated compact footprint of 8 μm × 2160 μm. Such excellent performances make ITO a strong candidate for low-loss TO phase shifters and open up an alternative method for realizing ultrafast and high-speed mode division multiplexing systems and large-scale applications.
We design an ultracompact, broadband, and low-loss 90-deg optical hybrid coupler using a silicon-on-insulator (SOI) material platform for coherent receivers in optical communication systems. The proposed hybrid coupler uses a cascaded topology that includes five 2 × 2 multimode interference (MMI) couplers in three different fundamental kinds. The working principle of the suggested 90-deg optical hybrid is based on theoretical analysis on the MMI effect and the transfer matrix relations. The optimization of geometrical parameters and the optical characteristics are employing through the numerical simulation method. The investigated 90-deg optical hybrid coupler can be integrated on a microscale footprint as much as 6 μm × 172 μm. Furthermore, our hybrid coupler expresses lots of advantages of optical performances, with an insertion loss lower than 2.6 dB, a common-mode rejection ratio better than −25 dB, and phase error smaller than 5 deg in 90-nm wavelength-bandwidth in the third telecom window. In addition, the designed device, based on the SOI platform, is endowed with large geometrical tolerances possessing width, height, and multimode tolerances corresponding to ±20, ±10, and ±10 nm in the 1-dB variation limit of transmission, respectively. Such advantages of good performances thus make the proposed hybrid device playing the role of a promising potential candidate for widely varying applications of silicon photonics, such as coherent optical receivers, optical interconnects, and high-bitrate optical phase modulators.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.