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Visualizing Uniaxial-strain Manipulation of Antiferromagnetic Domains in Fe1+YTe Using a Spin-polarized Scanning Tunneling Microscope
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Dichotomy between the Hole and Electron Behavior in Multiband Superconductor FeSe Probed by Ultrahigh Magnetic Fields
M D Watson1, T Yamashita2, S Kasahara2
1Clarendon Laboratory, Department of Physics, University of Oxford, Parks Road, Oxford OX1 3PU, United Kingdom.
Physical Review Letters
|July 25, 2015
Summary
Quantum oscillations in FeSe reveal a multiband electronic structure. Magnetotransport measurements identified a dominant hole band and an additional small electron pocket in this superconductor.
Area of Science:
- Condensed Matter Physics
- Materials Science
Background:
- Superconducting FeSe exhibits complex electronic properties.
- Understanding its multiband electronic structure is crucial for its application.
Purpose of the Study:
- To elucidate the multiband electronic structure of superconducting FeSe.
- To identify the charge carrier types and their respective Fermi surface contributions.
Main Methods:
- Magnetoresistivity (ρ(xx)) and Hall resistivity (ρ(xy)) measurements.
- Utilized ultrahigh magnetic fields (up to 88 T) and low temperatures (down to 0.15 K).
- Developed a novel approach to determine charge carrier signs from magnetotransport data.
Main Results:
- Observed quantum oscillations in both ρ(xx) and ρ(xy), confirming small-volume Fermi surface pockets.
- Differentiated oscillation amplitudes in ρ(xx) and ρ(xy) to identify the largest pocket as a hole band.
- Identified an additional tiny, high-mobility electron pocket in the orthorhombic phase of FeSe.
Conclusions:
- FeSe possesses a multiband electronic structure with both hole and electron carriers.
- The findings provide critical insights into the electronic behavior of FeSe under extreme conditions.
- The proposed method offers a new way to analyze compensated metals.
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