Modulation above Pump Beam Energy in Photoreflectance

Figure 2

PR spectra of n-GaAs wafer obtained under different pump beam energies and pass filters. Dotted lines indicate the nominal wavelength of the pump beams. Critical points E₀, E₀ + Δ₀ (labeled as E_SO), and E₁ are also indicated. (Upper panel) using 325 nm pump with LPF 395 nm and additional LPF 665 nm or SPF 600 nm. (Middle panel) using 632.8 nm pump with LPF 665 nm or SPF 600 nm. (Lower panel) using 814 nm pump and SPF 800 nm.