Tailoring potentials by simulation-aided design of gate layouts for spin qubit applications

TL;DR

This paper introduces a simulation-based method for designing and optimizing gate layouts in spin qubit devices, addressing the need for scalable modeling as device complexity grows, and verifying the approach through experimental measurements.

Contribution

It presents a general electrostatic modeling approach for spin qubit device layouts, incorporating various device parameters and validating through transport measurements.

Findings

Model accurately predicts potential landscapes in spin qubit devices.

Simulation helps identify critical design areas for robustness.

Optimized layouts improve device yield and performance.

Abstract

Gate-layouts of spin qubit devices are commonly adapted from previous successful devices. As qubit numbers and the device complexity increase, modelling new device layouts and optimizing for yield and performance becomes necessary. Simulation tools from advanced semiconductor industry need to be adapted for smaller structure sizes and electron numbers. Here, we present a general approach for electrostatically modelling new spin qubit device layouts, considering gate voltages, heterostructures, reservoirs and an applied source-drain bias. Exemplified by a specific potential, we study the influence of each parameter. We verify our model by indirectly probing the potential landscape of two design implementations through transport measurements. We use the simulations to identify critical design areas and optimize for robustness with regard to influence and resolution limits of the fabrication process.