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.

中文翻译：

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通过操纵集成在绝缘体上硅波导上的基于 ITO 的可控移相器，对高度紧凑的宽带光学三模选择转换器进行数值设计和优化

最近，由于其高透明度、强 TO 相位依赖性、高导电性和 CMOS 兼容性，氧化铟锡对热光 (TO) 控制的硅光子器件非常有吸引力。这些特性能够减少硅芯和加热器之间的间隙，从而实现相当低的电力消耗和高开关速度。我们对数值模拟进行了研究，以设计和优化紧凑型 ITO 微型加热器，用于在具有宽带和超低损耗特性的三模转换器 (TMC) 的概念验证中调整 TO 相移。我们表明 TMC 可以操作高达 100 nm 的 3-dB 带宽。此外，所设计的器件在宽度和高度分别为±50 和±5 nm 时可以获得相对较大的制造公差。此外，所提出的模式转换器消耗的总功率小于 90 mW，并获得小于 8 μs 的快速开关时间。此外，该器件可以集成到估计的 8 μm × 2160 μm 的紧凑尺寸中。如此优异的性能使 ITO 成为低损耗 TO 移相器的有力候选者，并为实现超快和高速模分复用系统和大规模应用开辟了另一种方法。