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arXiv · 2504.04513

Environment-Assisted Generation of Non-Gaussian Wavepacket Quantum States

Maryam Khanahmadi·Klaus Mølmer
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Abstract

Generating non-Gaussian states and converting them into traveling wavepackets is crucial yet challenging for scalable, fault-tolerant quantum computing. We present a hardware-efficient approach that simultaneously achieves both tasks by combining an engineered nonlinear dissipation with a linear transmission loss from a superconducting circuit to a waveguide. This combination of dissipative channels leverages low-order interactions to induce a high-order nonlinearity, enabling deterministic emission of a wide range of non-Gaussian, error-correctable states, such as Schr\"odinger cat states, GKP states, and pair-cat states. We identify experimental superconducting circuit platforms and realistic parameter regimes for our proposal.

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Maryam Khanahmadi, Klaus Mølmer. 2025-04-06. Environment-Assisted Generation of Non-Gaussian Wavepacket Quantum States. https://doi.org/10.1103/dtd2-4vpn

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