A Novel Graphene/MoS 2 Heterojunction as Broadband Infrared Photodetector

Photodetectors with excellent detecting properties over a broad spectral range have wide application in many optoelectronic devices. Previously, various semiconducting photodetectors were introduced for detecting different sub-bands within the ultraviolet to near-infrared range, including GaN (ultraviolet), Si (visible), and PbS/InGaAs (near-infrared) detectors. However, the photodetectors with broadband spectra response and high detectivity at room temperature are favorable, especially in some typical applications such as the advanced multi-spectral detection and visible to mid-infrared digital cameras. As we know, the detectable light wavelength of a semiconducting material is dependent on its bandgap. In order to broaden the response spectral range of a separate photodetector, we need to resort to other semiconductors with more narrow bandgap.