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Topological Phonons and Weyl Lines in Three Dimensions
Olaf Stenull1, C L Kane1, T C Lubensky1
1Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
Physical Review Letters
|August 20, 2016
Summary
Researchers explored topological mechanics and phononics using generalized pyrochlore lattices. These structures exhibit protected edge states and Weyl lines, resulting in unique zero surface modes that shift with surface wave number.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Topological Physics
Background:
- Topological mechanics and phononics are emerging fields.
- These fields explore exotic states of matter with unique properties.
Purpose of the Study:
- To introduce and study generalizations of the three-dimensional pyrochlore lattice.
- To investigate the existence of topologically protected edge states and Weyl lines.
Main Methods:
- Theoretical modeling of generalized pyrochlore lattices.
- Analysis of bulk phonon spectra.
- Investigation of edge states and surface modes.
Main Results:
- Identified generalized pyrochlore lattices with topologically protected edge states.
- Discovered Weyl lines in the bulk phonon spectra.
- Observed zero surface modes that exhibit edge-to-edge flipping behavior dependent on surface wave number.
Conclusions:
- The studied pyrochlore lattice generalizations offer a platform for realizing topological phenomena in phononics.
- The findings contribute to the understanding of topological states in mechanical and phononic systems.
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