Advances in Materials Science and Engineering (Jan 2017)
Theoretical Study of High-Frequency Response of InGaAs/AlAs Double-Barrier Nanostructures
Abstract
The presented article contains the numerical calculations of the InGaAs/AlAs resonant tunneling diode’s (RTD) response to the AC electric field of a wide range of amplitudes and frequencies. These calculations have been performed within the coherent quantum-mechanical model that is based on the solution of the time-dependent Schrödinger equation with exact open boundary conditions. It is shown that as the field amplitude increases, at high frequencies, where ħω>Γ (Γ is the width of the resonant energy level), the active current can reach high values comparable to the direct current value in resonance. This indicates the implementation of the quantum regime for RTD when radiative transitions are between quasi-energetic levels and the resonant energy level. Moreover, there is an excitement of higher quasi-energetic levels in AC electric fields, which in particular results in a slow droop of the active current as the field amplitude increases. It also results in potentially abrupt changes of the operating point position by the ħω value. This makes it possible to achieve relatively high output powers of InGaAs/AlAs RTD having an order of 105 W/cm2 at high frequencies.