Consistent simulation of quantum devices incorporating GaAs/AlGaAs heterostructures

In quantum nanoelectronics and quantum information devices, electrostatic gates control the density of the electrons and the state of the qubits¹. In order to reliably predict the device characteristics, a consistent simulation method is required. In this work, a simulation model was created, that is able to self-consistently calculate the density of electrons aggregated at the interface of a GaAs/AlGaAs heterostructure by solving the Poisson and Schrödinger equations iteratively. The model was benchmarked with experimentally measured Quantum Point Contacts (QPC) of up to 27 different shapes. By solving the 3D problem, we were able to simulate the voltages at which the quantum channels become depleted as a function of the QPC shape to a very good accuracy. The variables that define the problem were captured in a minimal model, that can be used to predict the values of the parameters used in the simulation from basic wafer characteristics.

1. Bäuerle, C., Christian Glattli, D., Meunier, T., Portier, F., Roche, P., Roulleau, P., Takada, S., & Waintal, X. (2018). Coherent control of single electrons: A review of current progress. Reports on Progress in Physics, 81(5).