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Free spin quantum computation with semiconductor nanostructures

Wei-Min Zhang·Yin-Zhong Wu·Chopin Soo
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Abstract

Taking the excess electron spin in a unit cell of semiconductor multiple quantum-dot structure as a qubit, we can implement scalable quantum computation without resorting to spin-spin interactions. The technique of single electron tunnelings and the structure of quantum-dot cellular automata (QCA) are used to create a charge entangled state of two electrons which is then converted into spin entanglement states by using single spin rotations. Deterministic two-qubit quantum gates can also be manipulated using only single spin rotations with help of QCA. A single-short read-out of spin states can be realized by coupling the unit cell to a quantum point contact.

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Wei-Min Zhang, Yin-Zhong Wu, Chopin Soo. 2005-02-01. Free spin quantum computation with semiconductor nanostructures. https://arxiv.org/abs/quant-ph/0502002

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