Different-mode power splitters based on a multi-dimension direct-binary-search algorithm

In this work, we design, fabricate, and characterize a different-mode (waveguideconnected) power splitter ((W)PS) by what we believe to be a novel multi-dimension directbinary-search algorithm that can significantly balance the device performance, time cost, and fabrication robustness by searching the state-dimension, rotation-dimension, shape-dimension, and size-dimension parameters. The (W)PS can simultaneously generate the fundamental transverse electric (TE0) and TE1 mode with the 1:1 output balance. Compared with the PS, the WPS can greatly shorten the adiabatic taper length between the single-mode waveguide and the grating coupler. The measured results of the different-mode (W)PS indicate that the insertion loss and crosstalk are less than 0.9 (1.3) dB and lower than -17.8 (-14.9) dB from 1540 nm to 1560 nm. In addition, based on the tunable tap couplers, the different-mode (W)PS can be extended to multiple output ports with different modes and different transmittances.

Automated summary

In this research, we developed a different-mode power splitter (WPS) using a novel multi-dimension direct-binary-search algorithm. The WPS is capable of generating multiple modes simultaneously with a balanced output. Compared to the traditional power splitter, the WPS has a shorter adiabatic taper length and exhibits lower insertion loss and crosstalk. Additionally, by utilizing tunable tap couplers, the WPS can be extended to multiple output ports with different modes and transmittances.