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arXiv:quant-ph/0507037

Generation and Manipulation of Entanglement in Quantum Optical Systems

Dan E. Browne

Published Jul 4, 2005• 1 citation
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Abstract

In this thesis, several new procedures for the generation and manipulation of entangled states in quantum optical systems are introduced. Each is evaluated in terms of realistic models of the imperfect apparatus of any real laboratory implementation. The first half of the thesis considers entanglement generation in Cavity QED, introducing several proposals for the creation of maximally entangled two-qubit states. The second half of the thesis focuses on the manipulation of entangled states of light pulses. In particular, an entanglement distillation procedure for Gaussian states is introduced. This combines a Procrustean protocol for the generation of highly entangled non-Gaussian states, with a "Gaussification" procedure, which allows more highly entangled approximately Gaussian states to be distilled from a non-Gaussian supply.

DOI
10.48550/arxiv.quant-ph/0507037

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The entanglement between Gaussian entangled states can be increased by non-Gaussian operations. We design a new scheme, named coherent photon addition, which can coherently add one photon generated by a spontaneous parametric down-conversation process to Gaussian quadrature-entangled light pulses created by a non-degenerate optical parametric amplifier. This operation can increase the entanglement of input two-mode Gaussian states as an entanglement distillation, and provides us with a new method of non-Gaussian operation. This scheme can also help us to study the decoherence of adding one- to two-mode Gaussian states from coherent photon addition to normal photon addition.
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