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Coherent optical control of the spin of a single hole in a quantum dot

Godden, Timothy Mark (2012) Coherent optical control of the spin of a single hole in a quantum dot. PhD thesis, University of Sheffield.

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Abstract

This thesis describes experiments on the initialisation, coherent control, and readout of a single hole spin trapped in a self assembled InGaAs semiconductor quantum dot. High fidelity initialisation of a hole spin state is achieved by the fast ionisation of a spin polarised neutral exciton under an applied electric field and in a Faraday geometry magnetic field. The preparation of a coherent superposition state is demonstrated by observing the precession of the hole spin about a Voigt geometry magnetic field. The hole spin dephasing time is deduced from the decay of the spin contrast. Coherent optical rotation of the hole spin state about the z-axis is demonstrated using the geometric phase shift induced by a picosecond laser pulse. By combining the precession of the spin about the x-axis, and optical rotations about the z-axis, full quantum control of a hole spin is demonstrated over the surface of the Bloch sphere. This is an important prerequisite for the use of a hole spin as a qubit for quantum information processing applications.

Item Type: Thesis (PhD)
Academic Units: The University of Sheffield > Faculty of Science (Sheffield) > Physics and Astronomy (Sheffield)
Depositing User: Dr Timothy Mark Godden
Date Deposited: 11 Apr 2012 10:44
Last Modified: 08 Aug 2013 08:48
URI: http://etheses.whiterose.ac.uk/id/eprint/2190

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