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arXiv · 2206.06059

Realization of high-fidelity unitary operations on up to 64 frequency bins

Syamsundar De·Vahid Ansari·Jan Sperling·Sonja Barkhofen·Benjamin Brecht·Christine Silberhorn
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Abstract

The ability to apply user-chosen large-scale unitary operations with high fidelity to a quantum state is key to realizing future photonic quantum technologies. Here, we realize the implementation of programmable unitary operations on up to 64 frequency-bin modes. To benchmark the performance of our system, we probe different quantum walk unitary operations, in particular Grover walks on four-dimensional hypercubes with similarities exceeding 95\% and quantum walks with 400 steps on circles and finite lines with similarities of 98\%. Our results open a new path towards implementing high-quality unitary operations, which can form the basis for applications in complex tasks, such as Gaussian boson sampling.

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Syamsundar De, Vahid Ansari, Jan Sperling, Sonja Barkhofen, Benjamin Brecht, Christine Silberhorn. 2022-06-13. Realization of high-fidelity unitary operations on up to 64 frequency bins. https://arxiv.org/abs/2206.06059

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