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arXiv · 2601.23028

High-resolution tunable frequency beamsplitter enabled by an integrated silicon pulse shaper

Chen-You Su·Kaiyi Wu·Lucas M. Cohen·Saleha Fatema·Navin B. Lingaraju·Hsuan-Hao Lu·Andrew M. Weiner·Joseph M. Lukens·Jason D. McKinney
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Abstract

We demonstrate high-fidelity, tunable, and ultrafine-resolution on-chip frequency beamsplitters using a quantum frequency processor based on an integrated pulse shaper with six spectral channels. Near-ideal Hadamard gate performance is achieved, with fidelity F > 0.9995 and modified success probability P > 0.9621 maintained across frequency spacings from 2-5 GHz and down to as few as four spectral pulse shaper channels. The system's support of frequency spacings as narrow as 2 GHz significantly surpasses prior bulk demonstrations and enables arbitrary splitting ratios via spectral phase or modulation index control. These results establish a scalable and resource-efficient platform for integrated frequency-bin quantum photonics, opening new directions in quantum information processing, including densely parallel single-qubit operations and multidimensional gate implementations.

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Chen-You Su, Kaiyi Wu, Lucas M. Cohen, Saleha Fatema, Navin B. Lingaraju, Hsuan-Hao Lu, Andrew M. Weiner, Joseph M. Lukens, Jason D. McKinney. 2026-01-30. High-resolution tunable frequency beamsplitter enabled by an integrated silicon pulse shaper. https://arxiv.org/abs/2601.23028

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