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arXiv · 0802.1874

Perturbative Gadgets at Arbitrary Orders

Stephen P. Jordan·Edward Farhi
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Abstract

Adiabatic quantum algorithms are often most easily formulated using many-body interactions. However, experimentally available interactions are generally two-body. In 2004, Kempe, Kitaev, and Regev introduced perturbative gadgets, by which arbitrary three-body effective interactions can be obtained using Hamiltonians consisting only of two-body interactions. These three-body effective interactions arise from the third order in perturbation theory. Since their introduction, perturbative gadgets have become a standard tool in the theory of quantum computation. Here we construct generalized gadgets so that one can directly obtain arbitrary k-body effective interactions from two-body Hamiltonians. These effective interactions arise from the kth order in perturbation theory.

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Stephen P. Jordan, Edward Farhi. 2008-02-13. Perturbative Gadgets at Arbitrary Orders. https://doi.org/10.1103/physreva.77.062329

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