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Resonant Quantum Search with Monitor Qubits

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 نشر من قبل Hong-Ye Hu
 تاريخ النشر 2020
  مجال البحث فيزياء
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We present an algorithm for the generalized search problem (searching $k$ marked items among $N$ items) based on a continuous Hamiltonian and exploiting resonance. This resonant algorithm has the same time complexity $O(sqrt{N/k})$ as the Grover algorithm. A natural extension of the algorithm, incorporating auxiliary monitor qubits, can determine $k$ precisely, if it is unknown. The time complexity of our counting algorithm is $O(sqrt{N})$, similar to the best quantum approximate counting algorithm, or better, given appropriate physical resources.

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