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Effect of Quantum Fluctuations in an Ising System on Small-World Networks

Hangmo Yi·Mahn-Soo Choi
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Abstract

We study quantum Ising spins placed on small-world networks. A simple model is considered in which the coupling between any given pair of spins is a nonzero constant if they are linked in the small-world network and zero otherwise. By applying a transverse magnetic field, we have investigated the effect of quantum fluctuations. Our numerical analysis shows that the quantum fluctuations do not alter the universality class at the ferromagnetic phase transition, which is of the mean-field type. The transition temperature is reduced by the quantum fluctuations and eventually vanishes at the critical transverse field $Δ_c$. With increasing rewiring probability, $Δ_c$ is shown to be enhanced.

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Hangmo Yi, Mahn-Soo Choi. 2002-12-11. Effect of Quantum Fluctuations in an Ising System on Small-World Networks. https://doi.org/10.1103/physreve.67.056125

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