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Lanczos exact diagonalization study of field-induced phase transition for Ising and Heisenberg antiferromagnets

Seung-Pyo Hong·Choong-Seok Kim·Sung-Sik Lee·Sung-Ho Suck Salk
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Abstract

Using an exact diagonalization treatment of Ising and Heisenberg model Hamiltonians, we study field-induced phase transition for two-dimensional antiferromagnets. For the system of Ising antiferromagnet the predicted field-induced phase transition is of first order, while for the system of Heisenberg antiferromagnet it is the second-order transition. We find from the exact diagonalization calculations that the second-order phase transition (metamagnetism) occurs through a spin-flop process as an intermediate step.

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Seung-Pyo Hong, Choong-Seok Kim, Sung-Sik Lee, Sung-Ho Suck Salk. 1999-01-21. Lanczos exact diagonalization study of field-induced phase transition for Ising and Heisenberg antiferromagnets. https://doi.org/10.1103/physrevb.60.9252

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