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

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.

5 pages, 4 figures, accepted in Journal of Physics B

References in corpus (6)

• Optical Quantum Computing
• Silica-on-Silicon Waveguide Quantum Circuits
• Experimental implementation of the optimal linear-optical controlled phase gate
• On photonic controlled phase gates
• Preparation of entangled states of two photons in several spatial modes
• Optimal state in the Knill-Laflamme-Milburn scheme of linear optical teleportation

Cited by in corpus (3)

• Engineering steady Knill-Laflamme-Milburn state of Rydberg atoms by dissipation
• Preparation of Knill-Lafamme-Milburn states based on superconducting qutrits
• Scheme for a linear-optical controlled-phase gate with programmable phase shift