Nanoelectronic pulse generators based on gated resonant tunnelling diodes

摘要

We study the operation of a gated resonant tunnel diode placed in an oscillator tank circuit for application as a pulse generator. The gated diode is realized by a metal gate placed 30nm away from a resonant tunnelling double barrier heterostructure, where the gate is used to control the current of the tunnelling diode. A large signal model is developed for the gated resonant tunnelling diode and we use this model to study the operation of the pulsed oscillator. It is demonstrated that the gate can be used to switch the oscillations on and off and to tune the oscillation frequency via changes in the internal capacitances in the gated diode. A modulation in the oscillation frequency of 7.6 GHz around 220 GHz is obtained for a change in the gate bias from 0.2 to — 0.6V. Short pulses applied to the gate results in only four periods of oscillation with a broad power spectrum.