Quantum information processing in electrically defined Silicon triple quantum dot systems

Abstract

Quantum bits (qubits) operations in electrically defined Silicon (Si) triple quantum dots (TQDs) are computationally investigated to elevate the potential of TQD structure as a platform for quantum information processing. Employing a realistic Si$/$Si-germanium heterostructure as a target model, device simulations are conducted to secure an initialized qubit state. Basic programmability is verified through implementation of individual qubit operations and 2-qubit entangling operations between neighboring QDs. Constructing a gate sequence composed of 1-qubit and 2-qubit blocks, then, we not only generate three-qubit Greenberger–Horne–Zeilinger state, but also quantify the degradation of state fidelity under the inevitable inaccuracy which are incorporated in the dominant factors of spin-qubit Hamiltonian. Presenting engineering details that are hard to be carried by simulations based on the first principle theory, this work can be served as a practical guideline for designs of scalable quantum processors with electron spin-qubits in Si QD platforms.