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Spatially Encoded Pseudo-Pure States for NMR Quantum Information Processing

Yehuda Sharf·Timothy F. Havel·David G. Cory
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Abstract

Quantum information processing by liquid-state NMR spectroscopy uses pseudo-pure states to mimic the evolution and observations on true pure states. A new method of preparing pseudo-pure states is described, which involves the selection of the spatially labeled states of an ancilla spin with which the spin system of interest is correlated. This permits a general procedure to be given for the preparation of pseudo-pure states on any number of spins, subject to the limitations imposed by the loss of signal from the selected subensemble. The preparation of a single pseudo-pure state is demonstrated by carbon and proton NMR on 13C-labeled alanine. With a judicious choice of magnetic field gradients, the method further allows encoding of up to 2^N pseudo-pure states in independent spatial modes in an N+1 spin system. Fast encoding and decoding schemes are demonstrated for the preparation of four such spatially labeled pseudo-pure states.

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Yehuda Sharf, Timothy F. Havel, David G. Cory. 2000-05-17. Spatially Encoded Pseudo-Pure States for NMR Quantum Information Processing. https://doi.org/10.1103/physreva.62.052314

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