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Combination of Ferromagnetic and Antiferromagnetic Features in Heisenberg Ferrimagnets

Shoji Yamamoto·Takahiro Fukui·Klaus Maisinger·Ulrich Schollwöck
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Abstract

We investigate the thermodynamic properties of Heisenberg ferrimagnetic mixed-spin chains both numerically and analytically with particular emphasis on the combination of ferromagnetic and antiferromagnetic features. Employing a new density-matrix renormalization-group technique as well as a quantum Monte Carlo method, we reveal the overall thermal behavior: At very low temperatures, the specific heat and the magnetic susceptibility times temperature behave like $T^{1/2}$ and $T^{-1}$, respectively, whereas at intermediate temperatures, they exhibit a Schottky-like peak and a minimum, respectively. Developing the modified spin-wave theory, we complement the numerical findings and give a precise estimate of the low-temperature behavior.

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Shoji Yamamoto, Takahiro Fukui, Klaus Maisinger, Ulrich Schollwöck. 1998-06-28. Combination of Ferromagnetic and Antiferromagnetic Features in Heisenberg Ferrimagnets. https://doi.org/10.1088/0953-8984%2F10%2F48%2F023

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