Low-temperature thermodynamics of one-dimensional alternating-spin Heisenberg ferromagnets

Shoji Yamamoto; Hiromitsu Hori

doi:10.1103/physrevb.72.054423

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Low-temperature thermodynamics of one-dimensional alternating-spin Heisenberg ferromagnets

Shoji Yamamoto·Hiromitsu Hori

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Abstract

Motivated by a novel bimetallic chain compound in which alternating magnetic centers are ferromagnetically coupled, we investigate thermodynamic properties of one-dimensional spin-$(S,s)$ Heisenberg ferromagnets both numerically and analytically. On the one hand, quantum Monte Carlo calculations illuminate the overall thermal behavior. The specific heat may exhibit a double-peaked structure at intermediate temperatures for $S\agt 3s$ in general. On the other hand, a modified spin-wave theory precisely describes the low-temperature properties. Expanding the specific heat and the magnetic susceptibility, we reveal an analogy and a contrast between mixed-spin ferromagnets and ferrimagnets.

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Shoji Yamamoto, Hiromitsu Hori. 2005-12-24. Low-temperature thermodynamics of one-dimensional alternating-spin Heisenberg ferromagnets. https://doi.org/10.1103/physrevb.72.054423

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