Ultraviolet Wavelength Identification Using Energy Distribution of Hot Electrons

[Image: see text] Light wavelength identification is essential for many optical and optoelectronic applications. Here, we report a novel wavelength identification photodetector based on the energy distribution of hot electrons at the metal/insulator interface. The information of the light wavelength can be stored in the energy distribution of the hot electrons, which can then be readout in the form of the current–voltage characteristics. On the basis of this principle, the high-reliability wavelength identification of the monochromatic light has been realized with a simple Al/SiO(2)/Si structure. The device has an excellent stability with dark current below 1 × 10(–7) A/m(2). Moreover, the wavelength of the monochromatic light in the deep ultraviolet range can be identified. This new principle will pave a new solution to design high-performance single-chip wavelength identification photodetectors and integrated miniaturized wavelength identification systems.