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arXiv · 2402.08551

Nonstabilizerness of Permutationally Invariant Systems

Gianluca Passarelli·Rosario Fazio·Procolo Lucignano
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Abstract

Typical measures of nonstabilizerness of a system of $N$ qubits require computing $4^N$ expectation values, one for each Pauli string in the Pauli group, over a state of dimension $2^N$. For permutationally invariant systems, this exponential overhead can be reduced to just $O(N^3)$ expectation values on a state with a dimension $O(N)$. We exploit this simplification to study the nonstabilizerness phase transitions of systems with hundreds of qubits.

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Gianluca Passarelli, Rosario Fazio, Procolo Lucignano. 2024-02-13. Nonstabilizerness of Permutationally Invariant Systems. https://doi.org/10.1103/physreva.110.022436

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