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arXiv · 2604.20118

Complexity of quantum states in the stabilizer formalism

Shuangshuang Fu·Shunlong Luo·Yue Zhang
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Abstract

We initiate an investigation into a notion of state complexity for discrete-variable quantum systems. Specifically, we propose an information-theoretic quantifier for the complexity of quantum states within the stabilizer formalism of quantum computation. This is achieved by leveraging the symmetric Jordan product (associated with classicality) and the skew-symmetric Lie product (linked to quantumness) between the square root of the quantum state and the Heisenberg-Weyl displacement operators. We establish the fundamental properties of this quantifier and demonstrate that state complexity is closely related to the nonstabilizerness of quantum states via the $L^4$-norm of their characteristic functions.

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Shuangshuang Fu, Shunlong Luo, Yue Zhang. 2026-04-22. Complexity of quantum states in the stabilizer formalism. https://arxiv.org/abs/2604.20118

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