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arXiv · 2605.18391

Reduced-State Stabilizer R\'enyi Entropy as a Probe of Quantum Criticality in the Transverse ANNNI Model and the Quantum Compass Model

Santanu Sarkar·George Biswas·Jun-Yi Wu·Anindya Biswas
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Abstract

We investigate the effectiveness of the stabilizer R\'enyi entropy (SRE), a quantifier associated with non-stabilizer resources (quantum magic), as an indicator of quantum phase transitions. Specifically, we analyze the behavior of the purity-corrected SRE of reduced density matrices in the ground states of two one-dimensional spin models: the transverse axial next-nearest-neighbor Ising (TANNNI) model and the quantum compass model (QCM). The ground state of the TANNNI model is obtained using exact diagonalization techniques, while the QCM is analyzed using the Jordan--Wigner (JW) transformation followed by Bogoliubov diagonalization of the resulting quadratic fermionic Hamiltonian. For the TANNNI model, the purity-corrected SRE successfully detects the antiphase--floating phase transition in the high-frustration regime, while in the low-frustration regime the raw (purity-uncorrected) SRE reproduces the known ferromagnetic--paramagnetic phase boundaries more accurately. For the QCM, the purity-corrected SRE exhibits a clear signature near the isotropic point \(J_x/J_z=1\), where the system undergoes a first-order quantum phase transition. Our results establish SRE of reduced states as a complementary probe of quantum criticality and provide further insight into the role of non-stabilizer resources in many-body quantum phase transitions.

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Santanu Sarkar, George Biswas, Jun-Yi Wu, Anindya Biswas. 2026-05-18. Reduced-State Stabilizer R\'enyi Entropy as a Probe of Quantum Criticality in the Transverse ANNNI Model and the Quantum Compass Model. https://arxiv.org/abs/2605.18391

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