Magnetic breakdown at high fields: semiclassical and quantum treatments
1Physics Department and NHMFL, Florida State University, Tallahassee, Florida 32310, USA.
Physical Review Letters
|September 6, 2000
Summary
This study investigates magnetic breakdown in organic conductors, finding agreement between quantum and semiclassical models. The Zeeman effect causes frequency splitting in de Haas-van Alphen oscillations.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Quantum Mechanics
Background:
- Magnetic breakdown (MB) is a quantum mechanical phenomenon observed in conductors under high magnetic fields.
- Understanding MB is crucial for characterizing electronic properties of materials.
- Organic conductors offer a unique platform for studying such phenomena due to their tunable structures.
Purpose of the Study:
- To investigate the effects of finite temperature and noninteracting spins on magnetic breakdown in quasi-two-dimensional organic conductors.
- To microscopically determine the field-dependent free energy and de Haas-van Alphen oscillation spectra.
- To compare semiclassical and quantum mechanical treatments of magnetic breakdown.
Main Methods:
- Computation of field-dependent free energy using a realistic crystal structure.
- Microscopic calculation of de Haas-van Alphen oscillation spectra.
- Analysis of magnetic breakdown phenomena under varying magnetic fields (170-1400 T).
Main Results:
- Remarkable agreement found between semiclassical and quantum treatments of magnetic breakdown.
- Finite temperature and noninteracting spins effects on MB were successfully determined.
- Zeeman effect was observed to cause frequency splitting in the fundamental orbit's de Haas-van Alphen oscillations.
Conclusions:
- The study validates the accuracy of both semiclassical and quantum models for describing magnetic breakdown in organic conductors.
- The findings provide a deeper microscopic understanding of electronic behavior in these materials.
- The observed Zeeman effect highlights its importance in interpreting de Haas-van Alphen measurements.
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