Abstract
The authors have experimentally investigated photoexcitation effects on carrier transports through a Ge quantum-dot (QD)∕SiO2 system via a resonant tunneling diode (RTD). Features of resonant oscillation and negative differential conductance are observed from the tunneling current of Ge-QDs RTDs at room temperature. The tunneling current not only displays additional oscillatory peaks but also exhibits enhanced peak-to-valley current ratio under photoexcitation. This indicates that holes created in the QD by photoexcitation lead to additional channels via the electron-hole interaction for electron tunneling through the QD. The exciton binding energy in the Ge QD could also be extracted from the voltage separation of the tunneling current peaks.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have