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arXiv · 0705.3688

Quantum computation in a Ising spin chain taking into account second neighbor couplings

G. V. López·T. Gorin·L. Lara
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Abstract

We consider the realization of a quantum computer in a chain of nuclear spins coupled by an Ising interaction. Quantum algorithms can be performed with the help of appropriate radio-frequency pulses. In addition to the standard nearest-neighbor Ising coupling, we also allow for a second neighbor coupling. It is shown, how to apply the 2πk method in this more general setting, where the additional coupling eventually allows to save a few pulses. We illustrate our results with two numerical simulations: the Shor prime factorization of the number 4 and the teleportation of a qubit along a chain of 3 qubits. In both cases, the optimal Rabi frequency (to suppress non-resonant effects) depends primarily on the strength of the second neighbor interaction.

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G. V. López, T. Gorin, L. Lara. 2007-05-25. Quantum computation in a Ising spin chain taking into account second neighbor couplings. https://doi.org/10.1007/s10773-007-9607-8

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