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Spatial Separation of Molecular Conformers and Clusters
Published on: January 9, 2014
Defect-mediated condensation of a charge density wave
Weitering1, Carpinelli, Melechko
1Department of Physics and Astronomy, University of Tennessee, Knoxville, TN 37996, USA. Solid State Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA. Department of Physics, Florida International University, University Park, Mia.
Science (New York, N.Y.)
|September 25, 1999
Summary
Point defects in two-dimensional charge density waves (CDWs) nucleate CDW domains. At low temperatures, disorder hopping mediated by CDWs reveals novel pinning center dynamics.
Area of Science:
- Condensed matter physics
- Materials science
Background:
- Critical phenomena are influenced by symmetry, dimensionality, and disorder.
- Charge density waves (CDWs) are key quantum states in low-dimensional materials.
Purpose of the Study:
- To directly visualize the interplay between charge density oscillations and lattice defects in a 2D CDW system.
- To understand the role of point defects in CDW formation and pinning.
Main Methods:
- Utilized scanning tunneling microscopy (STM) for atomic-scale imaging.
- Investigated a two-dimensional charge density wave (CDW) system.
Main Results:
- Observed point defects acting as nucleation centers for CDWs.
- Identified the formation of pinned CDW domains separated by charge boundaries upon cooling.
- Found evidence of incomplete freezing of substitutional disorder at low temperatures.
Conclusions:
- Point defects significantly influence CDW formation and domain structure.
- The observed phenomenon suggests a novel CDW-mediated hopping mechanism for pinning centers at low temperatures.
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