Fig. 1. k·p model-based theoretical band structure simulation

Fig. 2. Wavelength versus thickness relationship in InAs/InAs_1-xSb_x T2SLs with varying Sb compositions. (a) Wavelength dependence on InAs monolayer thickness；(b) Wavelength dependence on InAsSb monolayer thickness

Fig. 3. MBE epitaxial InAs/InAs_1-xSb_x T2SLs materials and sample measurement distribution

Fig. 4. Uniformity characterization of InAs/InAs_1-xSb_x T2SLs epitaxial wafer. (a) Comparative ω-2θ rocking curves from multiple measurement points；(b) Spatial distribution of superlattice period thickness；(c) Spatial variations of strain and Sb composition

Fig. 5. Schematic of AlAsSb layer growth optimization structure

Fig. 6. Surface morphology of AlAsSb layer at different growth temperatures. (a) 385 ℃; (b) 400 ℃; (c) 420 ℃

Fig. 7. Structural characterization of AlAs_1-xSb_x barrier layers. (a) ω-2θ scans of (004) plane for samples with varying Sb compositions；(b) Strain dependence on Sb composition and As/In flux ratio；(c) Reciprocal space mapping (RSM) of (224) plane

Fig. 8. Comparison of electrical performance for different passivation methods. (a) Dark current density versus bias characteristics；(b) Resistance-area product (RA) versus bias characteristics

Fig. 9. Variation of specific detectivity D* with wavelength