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The PSO algorithm is employed to iteratively optimize the device until the optimal solution is achieved. The device parameters obtained through PSO are presented in Table 1. Next, we evaluated the device performance via three-dimensional finite difference time domain (FDTD) simulation. The simulation results of the bi-level taper are illustrated in Figure 2(b), where the conversion efficiency of TM0-TE1 surpasses that within the wavelength range of 1260-1360nm. Additionally, the insertion loss of TM0 is less than ? dB, and that of TEO is less than ? dB.