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arXiv · 1108.1006

Preparation of Knill-Laflamme-Milburn states using tunable controlled phase gate

Karel Lemr
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Abstract

A specific class of partially entangled states known as Knill-Laflamme-Milburn states (or KLM states) has been proved to be useful in relation to quantum information processing [Knill et al., Nature 409, 46 (2001)]. Although the usage of such states is widely investigated, considerably less effort has been invested into experimentally accessible preparation schemes. This paper discusses the possibility to employ a tunable controlled phase gate to generate an arbitrary Knill-Laflamme-Milburn state. In the first part, the idea of using the controlled phase gate is explained on the case of two-qubit KLM states. Optimization of the proposed scheme is then discussed for the framework of linear optics. Subsequent generalization of the scheme to arbitrary n-qubit KLM state is derived in the second part of this paper.

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Karel Lemr. 2011-08-04. Preparation of Knill-Laflamme-Milburn states using tunable controlled phase gate. https://doi.org/10.1088/0953-4075/44/19/195501

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