Fig. 1. Schematic of light extinction of particle medium

Fig. 2. Extinction spectra of monodisperse Au-Ag alloy nanospheres with different particle sizes

Fig. 3. Variation curve of resonance wavelength with particle size of monodisperse Au-Ag alloy nanospheres

Fig. 4. Variation curve of absorbance ratio of two different wavelengths with particle size, λ₂ ranges fixed at 400 nm. （a） λ₁ ranges from 350-450 nm； （b） λ₁ ranges from 450-550 nm； （c） λ₁ ranges from 550-650 nm

Fig. 5. Variation curve of absorbance ratio of two different wavelengths with particle size, λ₂ ranges fixed at 600 nm. （a） λ₁ ranges from 350-450 nm； （b） λ₁ ranges from 450-550 nm； （c） λ₁ ranges from 550-650 nm

Fig. 6. Variation curve and fitted curve of the absorbance ratio with particle size of monodisperse Au-Ag alloy nanospheres at two fixed wavelengths

Fig. 7. Variation curve of the absorbance ratio of resonance wavelength to wavelength λ₂ with particle size. (a) λ₂ ranges from 350-450 nm; (b) λ₂ ranges from 450-550 nm; (c) λ₂ ranges from 550-650 nm

Fig. 8. Variation curve and fitted curve of the ratio of absorbance at resonance wavelength to 650 nm wavelength with particle size of monodisperse Au-Ag alloy nanospheres

Fig. 9. Variation curve and fitted curve of resonance wavelengths with minimum particle size of monodisperse Au-Ag alloy nanospheres