engleski

Charge density glass dynamics – soft potentials and soft modes

A very specific and universal fingerprint of glasses has been found in low-T thermodynamic properties of charge/spin density wave (C/SDW) systems. Deviations from the well-known Debye, elastic continuum prediction for specific heat (flat Cp/T3 plot) appear as two anomalies ; the upturn below 1 K and a broad bump at T~10 K (named Boson peak in glasses) [1]. The first one inherent of localized two level systems, within the shalow corrugated phase space, exhibits slow relaxation with the complex dynamics. The second one, „Boson peak-like peak“ was attributed to the pinned mode and incomplete softening of CDW superstructural mode. We discuss similar Cp(T) features found also in incommensurate dielectrics with well documented soft-mode („Kohn“) anomalies.

Charge and spin density waves; glasses; thermodynamics; soft potentials; soft mode

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