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arXiv · 2007.02385

Interference-based universal decoupling and swapping for multimode bosonic systems

Mengzhen Zhang·Shoumik Chowdhury·Liang Jiang
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Abstract

Beam-splitter operations are widely used to process information encoded in bosonic modes. In hybrid quantum systems, however, it might be challenging to implement a reliable beam-splitter operation between two distinct bosonic modes. Without beam-splitters, some basic operations such as decoupling modes and swapping states between modes can become highly non-trivial or not feasible at all. In this work, we develop novel interference-based protocols for decoupling and swapping selected modes of a multimode bosonic system without requiring beam-splitters. Specifically, for a given generic coupler characterized by a Gaussian unitary process, we show how to decouple a single mode or swap any pair of modes with a constant depth sequence of operations, while maintaining the coupling for the remaining system. These protocols require only multiple uses of the given coupler, interleaved with single-mode Gaussian unitary operations, and thus enable efficient construction of operations crucial to quantum information science, such as high-fidelity quantum transduction. Our results are directly derived from fundamental physical properties of bosonic systems and are therefore broadly applicable to various existing platforms.

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Mengzhen Zhang, Shoumik Chowdhury, Liang Jiang. 2020-10-19. Interference-based universal decoupling and swapping for multimode bosonic systems. https://arxiv.org/abs/2007.02385

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