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Entanglement distribution for a practical quantum-dot-based quantum processor architecture

Timothy P. Spiller·Irene D'Amico·Brendon W. Lovett
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Abstract

We propose a quantum dot architecture for enabling universal quantum information processing. Quantum registers, consisting of arrays of vertically stacked self-assembled semiconductor quantum dots, are connected by chains of in-plane self-assembled dots. We propose an entanglement distributor, a device for producing and distributing maximally entangled qubits on demand, communicated through in-plane dot chains. This enables the transmission of entanglement to spatially separated register stacks, providing a resource for the realisation of a sizeable quantum processor built from coupled register stacks of practical size. Our entanglement distributor could be integrated into many of the present proposals for self-assembled quantum dot-based quantum computation. Our device exploits the properties of simple, relatively short, spin-chains and does not require microcavities. Utilizing the properties of self-assembled quantum dots, after distribution the entanglement can be mapped into relatively long lived spin qubits and purified, providing a flexible, distributed, off-line resource.

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Timothy P. Spiller, Irene D'Amico, Brendon W. Lovett. 2007-04-13. Entanglement distribution for a practical quantum-dot-based quantum processor architecture. https://doi.org/10.1088/1367-2630%2F9%2F1%2F020

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