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arXiv · 2608.10604

Generating GKP states using quantum dots inside a strongly coupled cavity

Viswatma Kamath·Ravi Mehta·Biman Chattopadhyay·Sandeep K Goyal
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Abstract

GKP states enable fault-tolerant CV quantum computation, but their generation remains experimentally challenging due to their highly non-Gaussian and infinite-energy ideal structure. In this work, we present a realistic and scalable protocol for generating finite-energy resource states, specifically the qunaught state, using Schrodinger cat states generated in a strongly coupled quantum dot-cavity system. Our scheme combines deterministic squeezed cat-state generation, cat-breeding protocols, and homodyne measurements. Using numerical simulations, we analyze the role of various parameters of the quantum dot-cavity system in the generation of practical qunaught states. Furthermore, we quantify the trade-off between the fidelity and generation probability of these states and exploit the fact that accepting a structured set of homodyne outcomes can significantly enhance the overall success rate. The proposed approach is compatible with integrated photonics and telecom wavelengths, offering a promising route toward scalable CV quantum information processing.

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Viswatma Kamath, Ravi Mehta, Biman Chattopadhyay, Sandeep K Goyal. 2026-08-11. Generating GKP states using quantum dots inside a strongly coupled cavity. https://arxiv.org/abs/2608.10604

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