Compact spin qubits using the common gate structure of fin field-effect transistors

Abstract

The sizes of commercial transistors are of nanometer order, and there have already been many proposals of spin qubits using conventional complementary metal-oxide-semiconductor (CMOS) transistors. However, the previously proposed spin qubits require many wires to control a small number of qubits. This causes a significant 'jungle of wires' problem when the qubits are integrated into a chip. Herein, to reduce the complicated wiring, we theoretically consider spin qubits embedded into fin field-effect transistor (FinFET) devices such that the spin qubits share the common gate electrode of the FinFET. The interactions between qubits occur via the Ruderman-Kittel-Kasuya-Yosida (RKKY) interaction via the channel of the FinFET. The compensation for the compact implementation requires high-density current lines in a small space. The possibility of a quantum annealing machine is discussed in addition to the quantum computers of the current proposals. (i) S and drain voltage V(i) D (i ∈ N ).