An Effective Spin Hamiltonian Approach to Metamagnetism - I

P. Kumar; B. S. Shivaram; V. Celli

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arXiv · 1808.05658

An Effective Spin Hamiltonian Approach to Metamagnetism - I

P. Kumar·B. S. Shivaram·V. Celli

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Abstract

We describe a minimal model, based on a spin only Hamiltonian with a single energy scale for itinerant electron metamagnetism. Within this model the metamagnetic critical field is directly proportional to the temperature where a peak in the linear susceptibility occurs which in turn is related in a simple manner to the temperature where the nonlinear susceptibilities also peak. The spin dependent thermodynamic properties are derived in a straightforward manner and bear a striking resemblance to observations in such strongly correlated systems as heavy fermion materials. We also consider extensions of the model by including effects such as a mean field to encompass observed deviations from a minimal metamagnetic behavior.

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P. Kumar, B. S. Shivaram, V. Celli. 2018-08-16. An Effective Spin Hamiltonian Approach to Metamagnetism - I. https://arxiv.org/abs/1808.05658

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