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arXiv · 1710.10518

Quantum state engineering using one-dimensional discrete-time quantum walks

Luca Innocenti·Helena Majury·Taira Giordani·Nicolò Spagnolo·Fabio Sciarrino·Mauro Paternostro·Alessandro Ferraro
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Abstract

Quantum state preparation in high-dimensional systems is an essential requirement for many quantum-technology applications. The engineering of an arbitrary quantum state is, however, typically strongly dependent on the experimental platform chosen for implementation, and a general framework is still missing. Here we show that coined quantum walks on a line, which represent a framework general enough to encompass a variety of different platforms, can be used for quantum state engineering of arbitrary superpositions of the walker's sites. We achieve this goal by identifying a set of conditions that fully characterize the reachable states in the space comprising walker and coin, and providing a method to efficiently compute the corresponding set of coin parameters. We assess the feasibility of our proposal by identifying a linear optics experiment based on photonic orbital angular momentum technology.

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Luca Innocenti, Helena Majury, Taira Giordani, Nicolò Spagnolo, Fabio Sciarrino, Mauro Paternostro, Alessandro Ferraro. 2017-10-28. Quantum state engineering using one-dimensional discrete-time quantum walks. https://doi.org/10.1103/physreva.96.062326

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