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A convenient method to prepare the effective pure state in a quantum ensemble

Xijia Miao
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Abstract

A simple method is proposed to prepare conveniently the effective pure state |00...0><0...00| with any number of qubits in a quantum ensemble. The preparation is based on the temporal averaging (Knill, Chuang, and Laflamme, Phys.Rev.A 57, 3348(1998)). The quantum circuit to prepare the effective pure state is designed in a unified and systematical form and is explicitly decomposed completely into a product of a series of one-qubit quantum gates and the two-qubit diagonal quantum gates. The preparation could be programmed and implemented conveniently on an NMR quantum computer.

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Xijia Miao. 2000-08-23. A convenient method to prepare the effective pure state in a quantum ensemble. https://arxiv.org/abs/quant-ph/0008094

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