Quantum Computing in Diamond

Steven Prawer

Published May 28, 2007• 0 citations

Abstract

The aim of this proposal is to demonstrate the key elements needed to construct a logical qubit in diamond by exploiting the remarkable quantum properties of the nitrogen-vacancy (NV) optical centre. Specifically, the focus of the work was to address the materials and fabrication issues. We have demonstrated (i) that individual NV qubits can be fabricated by ion implantation with long coherence times (>350 microseconds at room temperature), (ii) electrical control of the optical output of each individual centre is achievable via the Stark shift, (iii) coherent population trapping of ensembles and single NV centres allowing for all-optical control of qubit operations and (iv) that waveguides, cavities and photonic band-gap structures can be fabricated in single crystal diamond. We have thus demonstrated a nanofabrication tool-kit for diamond which is sufficiently robust and mature to justify future investment in the design and implementation of a scalable quantum computing architecture for diamond.

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