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arXiv · 1808.08875

Experimental engineering of arbitrary qudit states with discrete-time quantum walks

Taira Giordani·Emanuele Polino·Sabrina Emiliani·Alessia Suprano·Luca Innocenti·Helena Majury·Lorenzo Marrucci·Mauro Paternostro·Alessandro Ferraro·Nicolò Spagnolo·Fabio Sciarrino
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Abstract

The capability to generate and manipulate quantum states in high-dimensional Hilbert spaces is a crucial step for the development of quantum technologies, from quantum communication to quantum computation. One-dimensional quantum walk dynamics represents a valid tool in the task of engineering arbitrary quantum states. Here we affirm such potential in a linear-optics platform that realizes discrete-time quantum walks in the orbital angular momentum degree of freedom of photons. Different classes of relevant qudit states in a six-dimensional space are prepared and measured, confirming the feasibility of the protocol. Our results represent a further investigation of quantum walk dynamics in photonics platforms, paving the way for the use of such a quantum state-engineering toolbox for a large range of applications.

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Taira Giordani, Emanuele Polino, Sabrina Emiliani, Alessia Suprano, Luca Innocenti, Helena Majury, Lorenzo Marrucci, Mauro Paternostro, Alessandro Ferraro, Nicolò Spagnolo, Fabio Sciarrino. 2018-08-27. Experimental engineering of arbitrary qudit states with discrete-time quantum walks. https://doi.org/10.1103/physrevlett.122.020503

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