Quantum computing and single-qubit measurements using the spin filter effect

David P. DiVincenzo

doi:10.1063/1.370481

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arXiv · cond-mat/9810295

Quantum computing and single-qubit measurements using the spin filter effect

David P. DiVincenzo

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Abstract

Many things will have to go right for quantum computation to become a reality in the lab. For any of the presently-proposed approaches involving spin states in solids, an essential requirement is that these spins should be measured at the single-Bohr-magneton level. Fortunately, quantum computing provides a suggestion for a new approach to this seemingly almost impossible task: convert the magnetization into a charge, and measure the charge. I show how this might be done by exploiting the spin filter effect provided by ferromagnetic tunnel barriers, used in conjunction with one-electron quantum dots.

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David P. DiVincenzo. 1998-10-22. Quantum computing and single-qubit measurements using the spin filter effect. https://doi.org/10.1063/1.370481

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