Based on electron spins in semiconductor quantum dots as qubits, a new quantum controlled-NOT(CNOT) gate is constructed in solid nanostructure without resorting to spin-spin interactions. Single electron tunneling technology and coherent quantum-dot cellular automata architecture are used to generate an ancillary charge entangled state. Using the ancillary charge entangled state as an intermediate state, we obtain a spin entangled state and design a CNOT gate by using only single spin rotations.
@article{arxiv.0708.2517,
title = {Implementing controlled-NOT gate based on free spin qubits with semiconductor quantum-dot array},
author = {Yin-Zhong Wu and Wei-Min Zhang},
journal= {arXiv preprint arXiv:0708.2517},
year = {2009}
}