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Orientational Transition in a Liquid Crystal Triggered by the Thermodynamic Growth of Interfacial Wetting Sheets
Published on: May 15, 2017
Electronic structure of solids with competing periodic potentials.
1Theoretische Physik 1, Universität Bayreuth, D-95440 Bayreuth, Germany. johannes.voit@uni-bayreuth.de
Science (New York, N.Y.)
|October 20, 2000
Summary
Electrons in potentials with two incommensurate periods unexpectedly exhibit dispersing band states. This phenomenon arises from the complex distribution of electronic spectral weight, challenging traditional physics expectations.
Area of Science:
- Condensed matter physics
- Quantum mechanics
- Materials science
Background:
- Electrons in potentials with incommensurate periods typically lose translational invariance.
- Periodic band structures are not expected under such conditions.
Purpose of the Study:
- To investigate the electronic band structure of quasi-one-dimensional materials subjected to potentials with two incommensurate periods.
- To reconcile theoretical predictions with experimental observations in such systems.
Main Methods:
- Model calculations using nearly free one-dimensional electrons.
- High-resolution photoemission spectroscopy on quasi-one-dimensional materials.
Main Results:
- Observed dispersing band states with signatures of both periodicities, contrary to expectations.
- Demonstrated that apparent band structures arise from nonuniform electronic spectral weight distribution.
Conclusions:
- The study reveals unexpected electronic band behavior in systems with incommensurate potentials.
- Nonuniform spectral weight distribution over complex eigenvalues generates observable band structures, challenging established theories.
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