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arXiv · 2411.00599

Continuous-variable square-ladder cluster states in a microwave frequency comb

Fabio Lingua·J. C. Rivera Hernández·Michele Cortinovis·David B. Haviland
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Abstract

We describe an experiment demonstrating the generation of three independent square-ladder continuous-variable cluster states with up to 94 qumodes of a microwave frequency comb. This entanglement structure at a large scale is realized by injecting vacuum fluctuations into a Josephson Parametric Amplifier pumped by three coherent signals around twice its resonance frequency, each having a particular well-defined phase relation. We reach up to 1.4 dB of squeezing of the nullifier which verifies the cluster state on the square ladder graph. Our results are consistent with a more familiar measure of two-mode squeezing, where we find up to 5.42 dB for one pump, and up to 1 dB for three pumps.

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Fabio Lingua, J. C. Rivera Hernández, Michele Cortinovis, David B. Haviland. 2024-11-01. Continuous-variable square-ladder cluster states in a microwave frequency comb. https://doi.org/10.1103/physrevlett.134.183602

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