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arXiv · 1708.08212

Fidelity Susceptibility Study of Quantum Long-Range Antiferromagnetic Ising Chain

Gaoyong Sun
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Abstract

We study the fidelity susceptibility of quantum antiferromagnetic Ising chain with a long-range power law interaction $1/r^α$ using the large-scale density matrix renormalization group method. We find that the critical adiabatic dimension $μ=2$ and the critical exponent of the correlation length $ν=1$ for arbitrary $α>0$, indicating all quantum phase transitions are second-order Ising transitions. In addition, we numerically determine the complete phase diagram for $0 < α\le 3$ from the data collapse of the fidelity susceptibility and show that the critical point $h_c$ changes monotonously with respect to $α$. This work will shed light on the nature of phase transitions in the quantum long-range antiferromagnetic Ising chain from a quantum information perspective.

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Gaoyong Sun. 2017-08-28. Fidelity Susceptibility Study of Quantum Long-Range Antiferromagnetic Ising Chain. https://doi.org/10.1103/physreva.96.043621

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