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arXiv · 1208.0706

Quantum phases of dimerized and frustrated Heisenberg spin chains with s = 1/2, 1 and 3/2: an entanglement entropy and fidelity study

V. M. L. Durga Prasad Goli·Shaon Sahoo·S. Ramasesha·Diptiman Sen
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Abstract

We study here different regions in phase diagrams of the spin-1/2, spin-1 and spin-3/2 one dimensional antiferromagnetic Heisenberg systems with frustration (next-nearest-neighbor interaction $J_2$) and dimerization ($δ$). In particular, we analyze the behaviors of the bipartite entanglement entropy and fidelity at the gapless to gapped phase transitions and across the lines separating different phases in the $J_2-δ$ plane. All the calculations in this work are based on numerical exact diagonalizations of finite systems.

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V. M. L. Durga Prasad Goli, Shaon Sahoo, S. Ramasesha, Diptiman Sen. 2013-02-01. Quantum phases of dimerized and frustrated Heisenberg spin chains with s = 1/2, 1 and 3/2: an entanglement entropy and fidelity study. https://doi.org/10.1088/0953-8984%2F25%2F12%2F125603

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