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arXiv · 1107.4394

Quasideterministic realization of a universal quantum gate in a single scattering process

F. Ciccarello·D. E. Browne·L. C. Kwek·H. Schomerus·M. Zarcone·S. Bose
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Abstract

We show that a flying particle, such as an electron or a photon, scattering along a one-dimensional waveguide from a pair of static spin-1/2 centers, such as quantum dots, can implement a CZ gate (universal for quantum computation) between them. This occurs quasi-deterministically in a single scattering event, hence with no need for any post-selection or iteration, {and} without demanding the flying particle to bear any internal spin. We show that an easily matched hard-wall boundary condition along with the elastic nature of the process are key to such performances.

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F. Ciccarello, D. E. Browne, L. C. Kwek, H. Schomerus, M. Zarcone, S. Bose. 2012-05-24. Quasideterministic realization of a universal quantum gate in a single scattering process. https://doi.org/10.1103/physreva.85.050305

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