Development of simulator for silicon quantum dot devices based on semiclassical device modeling

Recently, the novel design for qubit integration has been vigorously investigated for the realization of fault-tolerant quantum computers and the noisy intermediate-scale quantum (NISQ) technology. Silicon qubits have attracted much attention as a promising candidate for a building block of integrated quantum circuits because they can utilize cutting edge nanofabrication facilities for conventional logic devices. In order to develop the qubit suitable for large-integrated quantum circuits and design whole picture of quantum circuits and its peripheral control circuits, the simulation tool for supporting the qubit design is strongly required, like technology computer aided design (TCAD) for conventional transistor design. In this presentation, we report our recent development of a prototype simulator which can simulate the basic characteristics of silicon quantum dot devices as a basis of spin qubit. We utilize semi-classical device simulation as solvers of Poisson equation and classical current continuity equation combined with newly-developed tunneling and Coulomb-blockade models to calculate transport in quantum dot devices. As a demonstration of the simulation, we are going to show calculation examples of charge stability diagrams for some quantum dot devices.