Charge density glass dynamics - Soft potentials and soft modes

K. Biljaković (1) , D. Staresinic (1) , Jean-Claude Lasjaunias , Gyorgy Remenyi (2) , Régis Melin (3) , Pierre Monceau (2) , S. Sahling (4)

1 Institut of Physics-Zagreb
2 NEEL - MagSup - Magnétisme et Supraconductivité
3 NEEL - ThQC - Théorie Quantique des Circuits
4 Institut fur Festkorperphysics-Dresden

An universal fingerprint of glasses has been found in low-temperature thermodynamic properties of charge/spin density wave (C/SDW) systems. Deviations from the well-known Debye, elastic continuum prediction for specific heat (flat C-p/T-3 plot) appear as two anomalies; the upturn below 1 K and a broad bump at T similar to 10 K (named Boson peak in glasses). 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 C-p(T) features found also in incommensurate dielectrics with well documented soft-mode anomalies.

Domaines: Electrons fortement corrélés [cond-mat.str-el]

K. Biljaković, D. Staresinic, Jean-Claude Lasjaunias, Gyorgy Remenyi, Régis Melin, et al.. Charge density glass dynamics - Soft potentials and soft modes. Physica B: Condensed Matter, 2012, 407 (11), pp.1741-1745. ⟨10.1016/j.physb.2012.01.020⟩. ⟨hal-00966905⟩