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arXiv · 0704.0523

Quantum superpositions and entanglement of thermal states at high temperatures and their applications to quantum information processing

Hyunseok Jeong·Timothy C. Ralph
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Abstract

We study characteristics of superpositions and entanglement of thermal states at high temperatures and discuss their applications to quantum information processing. We introduce thermal-state qubits and thermal-Bell states, which are a generalization of pure-state qubits and Bell states to thermal mixtures. A scheme is then presented to discriminate between the four thermal-Bell states without photon number resolving detection but with Kerr nonlinear interactions and two single-photon detectors. This enables one to perform quantum teleportation and gate operations for quantum computation with thermal-state qubits.

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Hyunseok Jeong, Timothy C. Ralph. 2007-07-23. Quantum superpositions and entanglement of thermal states at high temperatures and their applications to quantum information processing. https://doi.org/10.1103/physreva.76.042103

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