Fig. 1. Schematic structure of the waveguide detector and optical beam propagation simulation

Fig. 2. Absorption coefficient and refractive index of InAs/GaAsSb superlattice

Fig. 3. (a) At a wavelength of 4.6 μm, the variation of waveguide loss with waveguide thickness, and the variation of quantum efficiency with waveguide thickness after the waveguide is integrated with the detector with a length of 200 μm, thicknesses of 0.7 μm, 0.95 μm and 1.2 μm respectively (the thickness here refers to the total thickness of the p-i-n structure, and only the thickness of the absorption layer is different); (b) the variation of quantum efficiency and responsivity of waveguide detector (absorption layer with a length of 200 μm, a thickness of 0.3μm) with wavelength; (c) the relationship between waveguide loss and wavelength

Fig. 4. The variation of quantum efficiency and responsivity with the (a) thickness and (b) length of the absorption layer at 4.6 μm

Fig. 5. The variation of NEP with the (a) thickness and (b) length of the absorption layer at 4.6 μm

Fig. 6. The variation of power with propagation length in waveguide detector （absorption layer with a length of 200 μm，a thickness of 0.3 μm） after 20 μm propagation in the waveguide