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arXiv · 2412.20396

Quantum Phase Transitions in the Spin 1 Bilinear-Biquadratic Heisenberg Model Based on Classical and Quantum Correlations

Ghader Najarbashi·Hassan Bahmani·Babak Tarighi
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Abstract

We investigate thermal and nonthermal quantum correlations in the one dimensional spin 1 bilinear-biquadratic Heisenberg model. Using tools from quantum information theory such as generalized concurrence, negativity, and various measures of quantum, classical, and total correlations in bipartite states we demonstrate that these measures effectively identify quantum phase transitions (QPTs) at critical points. Our negativity analysis reveals nearly identical results at zero or very low temperatures. Importantly, we find that partial concurrence, defined with the reduced density matrix, detects more quantum critical points than total concurrence. Additionally, we argue that spin chains with an odd number of spins are more effective than those with an even number in identifying QPTs.

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Ghader Najarbashi, Hassan Bahmani, Babak Tarighi. 2024-12-29. Quantum Phase Transitions in the Spin 1 Bilinear-Biquadratic Heisenberg Model Based on Classical and Quantum Correlations. https://arxiv.org/abs/2412.20396

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