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arXiv · 2601.12173

State Engineering via Nonlinear Interferometry with Linear Spectral Phases

Cody Charles Payne·Elaganuru Bashaiah·Markus Allgaier
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Abstract

Many protocols within quantum cryptography, communications, and computing require the ability to generate entangled states as well as spectral qudits. Nonlinear interferometry is a viable way to engineer these complex quantum states of light. However, it is difficult to achieve a high level of control over spectral correlations. Here, we present a protocol utilizing a nonlinear interferometer with linear spectral phases that can generate both high-dimensional spectral qudits and high-dimensional entangled states. We model the effect of loss and loss of overlap on interference visibility and thereby on the states generated.

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Cody Charles Payne, Elaganuru Bashaiah, Markus Allgaier. 2026-01-17. State Engineering via Nonlinear Interferometry with Linear Spectral Phases. https://doi.org/10.1364/oe.590780

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