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arXiv · 1702.07299

High-Dimensional Single-Photon Quantum Gates: Concepts and Experiments

Amin Babazadeh·Manuel Erhard·Feiran Wang·Mehul Malik·Rahman Nouroozi·Mario Krenn·Anton Zeilinger
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Abstract

Transformations on quantum states form a basic building block of every quantum information system. From photonic polarization to two-level atoms, complete sets of quantum gates for a variety of qubit systems are well known. For multi-level quantum systems beyond qubits, the situation is more challenging. The orbital angular momentum modes of photons comprise one such high-dimensional system for which generation and measurement techniques are well-studied. However, arbitrary transformations for such quantum states are not known. Here we experimentally demonstrate a four-dimensional generalization of the Pauli X-gate and all of its integer powers on single photons carrying orbital angular momentum. Together with the well-known Z-gate, this forms the first complete set of high-dimensional quantum gates implemented experimentally. The concept of the X-gate is based on independent access to quantum states with different parities and can thus be easily generalized to other photonic degrees-of-freedom, as well as to other quantum systems such as ions and superconducting circuits.

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Amin Babazadeh, Manuel Erhard, Feiran Wang, Mehul Malik, Rahman Nouroozi, Mario Krenn, Anton Zeilinger. 2017-02-23. High-Dimensional Single-Photon Quantum Gates: Concepts and Experiments. https://doi.org/10.1103/physrevlett.119.180510

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