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arXiv · 2011.01055

Success-or-Draw: A Strategy Allowing Repeat-Until-Success in Quantum Computation

Qingxiuxiong Dong·Marco Túlio Quintino·Akihito Soeda·Mio Murao
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Abstract

Repeat-until-success strategy is a standard method to obtain success with a probability which grows exponentially in the number of iterations. However, since quantum systems are disturbed after a quantum measurement, it is not straightforward how to perform repeat-until-success strategies in certain quantum algorithms. In this paper, we propose a new structure for probabilistic higher-order transformation named success-or-draw, which allows a repeat-until-success implementation. For that we provide a universal construction of success-or-draw structure which works for any probabilistic higher-order transformation on unitary operations. We then present a semidefinite programming approach to obtain optimal success-or-draw protocols and analyze in detail the problem of inverting a general unitary operation.

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Qingxiuxiong Dong, Marco Túlio Quintino, Akihito Soeda, Mio Murao. 2021-04-18. Success-or-Draw: A Strategy Allowing Repeat-Until-Success in Quantum Computation. https://doi.org/10.1103/physrevlett.126.150504

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