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Inhomogeneous ground state and the coexistence of two length scales near phase transitions in real solids

A. L. Korzhenevskii·K. Herrmanns·H. -O. Heuer
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Abstract

Real crystals almost unavoidably contain a finite density of dislocations. We show that this generic type of long--range correlated disorder leads to a breakdown of the conventional scenario of critical behavior and standard renormalization group techniques based on the existence of a simple, homogeneous ground state. This breakdown is due to the appearance of an inhomogeneous ground state that changes the character of the phase transition to that of a percolative phenomenon. This scenario leads to a natural explanation for the appearance of two length scales in recent high resolution small-angle scattering experiments near magnetic and structural phase transitions.

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A. L. Korzhenevskii, K. Herrmanns, H. -O. Heuer. 1998-05-28. Inhomogeneous ground state and the coexistence of two length scales near phase transitions in real solids. https://doi.org/10.1209/epl%2Fi1999-00146-1

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