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arXiv · 2402.03233

Spin-s Dicke states and their preparation

Rafael I. Nepomechie·Francesco Ravanini·David Raveh
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Abstract

We introduce the notion of $su(2)$ spin-$s$ Dicke states, which are higher-spin generalizations of usual (spin-1/2) Dicke states. These multi-qudit states can be expressed as superpositions of $su(2s+1)$ qudit Dicke states. They satisfy a recursion formula, which we use to formulate an efficient quantum circuit for their preparation, whose size scales as $sk(2sn-k)$, where $n$ is the number of qudits and $k$ is the number of times the total spin-lowering operator is applied to the highest-weight state. The algorithm is deterministic and does not require ancillary qudits.

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Rafael I. Nepomechie, Francesco Ravanini, David Raveh. 2024-02-05. Spin-s Dicke states and their preparation. https://doi.org/10.1002/qute.202400057

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