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Universal quantum computation with electron spins in quantum dots based on superpositions of spacetime paths and Coulomb blockade

Cyrus C. Y. Lin·Chopin Soo·Yin-Zhong Wu·Wei-Min Zhang
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Abstract

Using electrostatic gates to control the electron positions, we present a new controlled-NOT gate based on quantum dots. The qubit states are chosen to be the spin states of an excess conductor electron in the quantum dot; and the main ingredients of our scheme are the superpositions of space-time paths of electrons and the effect of Coulomb blockade. All operations are performed only on individual quantum dots and are based on fundamental interactions. Without resorting to spin-spin terms or other assumed interactions, the scheme can be realized with a dedicated circuit and a necessary number of quantum dots. Gate fidelity of the quantum computation is also presented.

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Cyrus C. Y. Lin, Chopin Soo, Yin-Zhong Wu, Wei-Min Zhang. 2004-10-20. Universal quantum computation with electron spins in quantum dots based on superpositions of spacetime paths and Coulomb blockade. https://arxiv.org/abs/quant-ph/0410150

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