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arXiv · 0806.0385

Adiabatic Quantum Computation with a 1D projector Hamiltonian

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Abstract

Adiabatic quantum computation is based on the adiabatic evolution of quantum systems. We analyse a particular class of qauntum adiabatic evolutions where either the initial or final Hamiltonian is a one-dimensional projector Hamiltonian on the corresponding ground state. The minimum energy gap which governs the time required for a successful evolution is shown to be proportional to the overlap of the ground states of the initial and final Hamiltonians. We show that such evolutions exhibit a rapid crossover as the ground state changes abruptly near the transition point where the energy gap is minimum. Furthermore, a faster evolution can be obtained by performing a partial adiabatic evolution within a narrow interval around the transition point. These results generalize and quantify earlier works.

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Avatar Tulsi. 2008-06-02. Adiabatic Quantum Computation with a 1D projector Hamiltonian. https://doi.org/10.1103/physreva.80.052328

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