Binding energy of exciton complexes determined by the tunneling current of single electron transistor under optical pumping

We theoretically study the tunnelling current of a single electron transistor (SET) under optical pumping. It found that holes in the quantum dot(QD) created by optical pumping lead to new channels for the electrons tunnelling from emitter to collector. As a consequence, an electron can tunnel through the QD via additional channels, characterized by the exciton, trion and biexciton states. The binding energy of exciton complexes can be determined by the Coulomb oscillatory tunnelling current.