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Computing with spins: From classical to quantum computing

S. Bandyopadhyay
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Abstract

This article traces a brief history of the use of single electron spins to compute. In classical computing schemes, a binary bit is represented by the spin polarization of a single electron confined in a quantum dot. If a weak magnetic field is present, the spin orientation becomes a binary variable which can encode logic 0 and logic 1. Coherent superposition of these two polarizations represent a qubit. By engineering the exchange interaction between closely spaced spins in neighboring quantum dots, it is possible to implement either classical or quantum logic gates.

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S. Bandyopadhyay. 2004-05-12. Computing with spins: From classical to quantum computing. https://doi.org/10.1016/j.spmi.2004.09.043

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