Multi-Color Detection of Single Sensor Based on Tellurium Relaxation Characteristics

Currently, multi-color detection is mostly limited by sophisticated optical filters, complex cell stacks, and the harsh input of single element detection. In this work, the relaxation characteristics of a single photodetector are used to detect multi-color light. First, a thin polycrystalline Te film was applied to fabricate a Te film photodetector exhibiting clear photoresponse relaxation. The results demonstrate how significantly diverse the relaxation processes are for excited states created by various wavelengths of excitation light. Finally, using the two current values at which relaxation starts and terminates, a vector ( ${I}_{\text {H}}$ , ${I}_{\text {L}}{)}$ is built to represent the relaxation features of light excitation at different wavelengths. The mapping relationship found in the test is used to calculate the wavelength and power information of incident light. This provides a successful demonstration of multicolored detection in a single device.