An X-ray study of charge-density-wave pinning and a measurement of the thermal conductivity in blue bronze

Two different aspects of the charge-density-wave (CDW) state were studied in the quasi-onedimensional metal blue bronze (Ko.3oMo03). In the primary experiment reported in this thesis, pinning of the CDW phase by lattice imperfections was examined. Pinning determines most of the dynamics of CDW systems and can be characterized by a phase coherence length L. Pinning sites were introduced into blue bronze by electron irradiation, then the anisotropy of L and its dependence on pinning site density npin were determined by high-resolution X-ray diffraction. The main results are that the phase coherence volume contains many pinning sites, and that the coherence length along two of the three directions measured decreases roughly as n;i~· 4 . A functional form for the phase coherence length along the third direction could not be determined. The results are compared to the predictions of various theories of pinning. In the secondary experiment, the temperature dependence of the thermal conductivity was measured by the absolute method. The change in the thermal conductivity at the CDW transition temperature is found to be in good agreement with that predicted by the Wiedemann-Franz law and by the measured electrical conductivity of blue bronze.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Physics

Year dc:date

2011

Author dc:creator

• DeLand, Sharon Marie

Contributors dc:contributor

• Mozurkewich, George

• charge-density-wave (CDW) state
• blue bronze
• thermal conductivity
• x-ray diffraction

Statement dc:rights

• 1991 Sharon Marie Deland

Language dc:language

en

Identifier

3476371

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/23871