Physics of Internal Photoemission and Its Infrared Applications in the Low-Energy Limit

Figure 7

(a) The experimental and model response [10] for detector sample SP003 at different biases and 300 K, due to the hole transition from heavy-hole () to spin-orbit split-off () bands. Both direct (~2.7 μm) and indirect (~3.25 μm) transition peaks were observed. (b) The 80 K responsivity spectra of SP001 at different biases. The light-hole () and heavy-hole () transition contribute to the long-wavelength region (>4 μm). A comparison of experiment with model free-carrier indirect responsivity (dashed line) for bias at 0.2 V is shown in the inset, indicating the - response superimposed on the free-carrier response.

(a)

(b)