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Quantum Phase Transitions in Spin Systems

J. Richter·S. E. Krüger·D. J. J. Farnell·R. F. Bishop
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Abstract

We discuss the influence of strong quantum fluctuations on zero-temperature phase transitions in a two-dimensional spin-half Heisenberg system. Using a high-order coupled cluster treatment, we study competition of magnetic bonds with and without frustration. We find that the coupled cluster treatment is able to describe the zero-temperature transitions in a qualitatively correct way, even if frustration is present and other methods such as quantum Monte Carlo fail.

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J. Richter, S. E. Krüger, D. J. J. Farnell, R. F. Bishop. 2001-05-27. Quantum Phase Transitions in Spin Systems. https://doi.org/10.1142/9789812799760_0022

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