Quantum dot photodetector apparatus and associated methods

A method of detecting incident electromagnetic radiation using an apparatus, the apparatus comprising a layer of channel material, source and drain electrodes configured to enable a flow of electrical current through the layer of channel material, and a layer of quantum dot material configured to generate electron-hole pairs on exposure to incident electromagnetic radiation to produce a detectable change in the electrical current which is indicative of one or more of the presence and magnitude of the electromagnetic radiation, wherein the layer of quantum dot material is positioned between the layer of channel material and a layer of conductive material, and wherein the layers of channel and conductive material have work functions such that respective built-in electric fields are created at the interfaces between the layer of quantum dot material and the layers of channel and conductive material, the built-in electric field at each interface acting in the same direction to promote separation of the electrons and holes of the generated electron-hole pairs to facilitate production of the detectable change in electrical current,

• the method comprising determining one or more of the presence and magnitude of the incident electromagnetic radiation based on a detected change in the flow of electrical current through the layer of channel material.