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Quantum oscillations in the topological superconductor candidate Cu(0.25)Bi2Se3
1Department of Physics, University of Michigan, Ann Arbor, Michigan 48109, USA.
Physical Review Letters
|February 2, 2013
Summary
Quantum oscillations were observed in the topological superconductor candidate Cu(0.25)Bi(2)Se(3) using torque magnetometry. This reveals insights into the electronic structure and Dirac-like band of this material.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Quantum Materials
Background:
- Topological insulators and superconductors are crucial for next-generation electronics.
- Quantum oscillations are vital for probing the electronic band structure of materials.
- Previous studies failed to observe quantum oscillations in Cu(0.25)Bi(2)Se(3) via conventional magnetotransport.
Purpose of the Study:
- To investigate the electronic structure of the topological superconductor candidate Cu(0.25)Bi(2)Se(3).
- To observe quantum oscillations (de Haas-van Alphen effect) in Cu(0.25)Bi(2)Se(3).
- To understand the impact of copper doping on the electronic properties of Bi(2)Se(3).
Main Methods:
- Torque magnetometry was employed to detect quantum oscillations.
- Magnetotransport measurements were performed for comparison.
- Analysis of the de Haas-van Alphen effect to determine electronic parameters.
Main Results:
- Quantum oscillations, specifically the de Haas-van Alphen effect, were successfully observed in Cu(0.25)Bi(2)Se(3).
- Copper doping increased carrier density and effective mass but did not affect scattering rate or mean free path.
- Fermi velocity remained unchanged, suggesting the band structure is preserved.
Conclusions:
- Torque magnetometry is a viable technique for observing quantum oscillations in materials where magnetotransport fails.
- The electronic band structure of Bi(2)Se(3) is largely maintained upon copper doping.
- Conduction electrons in Cu-doped Bi(2)Se(3) reside in a linear Dirac-like band, consistent with topological properties.
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