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Chinese Optics Letters

Non-unitary transformation on quantum interference in a chip

Jiani Lei, Yang Yilin, Hao Li, Zixuan Liao, Bo Tang, Yuanhua Li, Yuanlin Zheng, Xianfeng Chen

Published Jan 1, 2025• 0 citations
Publisher

Abstract

In quantum information processing, unitary transformations are oftentimes used to implement computing tasks.However, unitary transformations are not enough for all situations.Therefore, it is important to explore non-unitary transformations in quantum computing and simulation.Here, we introduce non-unitary transformations by performing singular value decomposition (SVD) on two-photon interference.Through simulation, we show that losses modeled by non-unitary transformation can be perceived as variables to control two-photon interference continuously, and the coincidence statistics can be changed by an appropriate choice of observation basis.The results are promising in the design of integrated optical circuits, providing a way toward fabricating large-scale programmable circuits.

DOI
10.3788/col202523.052701

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