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Continuous Versus First Order Transitions in Compressible Diluted Magnets

Yonathan Shapir·Serge Galam
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Abstract

The interplay between disorder and compressibility in Ising magnets is studied. Contrary to pure systems in which a weak compressibility drives the transition first order, we find from a renormalization group analysis that it has no effect on disordered systems which keep undergoing continuous transition with rigid random-bond Ising model critical exponents. The mean field calculation exhibits a dilution-dependent tricritical point beyond which, at stronger compressibility the transition is first order. The different behavior of XY and Heisenberg magnets is discussed.

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Yonathan Shapir, Serge Galam. 1996-06-17. Continuous Versus First Order Transitions in Compressible Diluted Magnets. https://doi.org/10.1016/0378-4371(95)00381-9

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