3D Stacked Spin Qubit by TCAD Simulations

Spin qubit systems are promising candidates for Si-based quantum computing. The conventional spin-qubit cell consists of control and readout units around a quantum dot (QD) with the excess electrons functioning as spin qubits. This complicates the integration of qubits because of the many wires and extra mechanisms, such as the requirement of shuttling parts. Therefore, we propose a new structure of stacked qubits, in which the gate-all-around (GAA) channel plays the role of both control and readout, and integration of qubits is feasible by extending the commercial silicon technologies. The qubit-QDs are placed in the gate insulator between the channel region and gate electrodes, similar to floating gates. Here, we present technology computer-aided design (TCAD) simulations to show how the extra electric charges in the QD affect the channel current.