Figure 3

Optoelectronic characterization of FIB fabricated Bi₂Te₃ nanowires. Inset in Fig. (a) represents the Bi₂Te₃ nanowire device (NW1) used for time and incident power dependent photocurrent measurements under UV and NIR light illuminations. The responsivity and detectivity curves obtained for UV, visible and NIR lights are shown in Fig. (b). The photocurrent dependence on incident power density (Fig. (c)) at different bias voltages and inset shows the responsivity curve. Fig. (d–f) represent the optoelectronic characterization for NW2 device (inset Fig. (d)). Fig. (d) shows the bias voltage dependent reponsivity curves observed for different wavelengths. The photocurrent measurement as a function of time in presence of visible and UV light illuminations at different bias voltages is shown in Fig. (e). Figure 3(f) shows NIR laser power density dependent photocurrent and responsivity curves. Inset represents the power density dependent detectivity curve.