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Scalable Quantum Integrated Circuits on Superconducting Two-Dimensional Electron Gas Platform
Published on: August 2, 2019
Quasi-two-dimensional Fermi surfaces and coherent interlayer transport in KFe₂As₂.
M Kimata1, T Terashima, N Kurita
1National Institute for Materials Science, Tsukuba, Ibaraki 305-0003, Japan.
Physical Review Letters
|January 15, 2011
Summary
Angular-dependent magnetoresistance oscillations revealed the Fermi surface (FS) shape in KFe2As2 superconductor. Two quasi-two-dimensional FSs with rounded-square cross sections were determined, offering insights into orbital contributions.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Superconductivity
Background:
- Understanding the Fermi surface (FS) is crucial for characterizing electronic properties of materials.
- Quasi-two-dimensional (Q2D) systems exhibit unique electronic behaviors due to their layered structure.
- Iron-based superconductors present complex phase diagrams and electronic structures.
Purpose of the Study:
- To determine the shape of bulk Fermi surfaces (FSs) in the highly hole-doped Fe-based superconductor KFe2As2.
- To investigate the electronic structure and orbital contributions to the FS in this material.
- To correlate FS topology with transport properties.
Main Methods:
- Angular-dependent magnetoresistance oscillations (AMROs) were employed to probe the FS.
- Interlayer transport measurements under in-plane magnetic fields were conducted.
- Analysis of oscillatory magnetoresistance data to extract FS geometry.
Main Results:
- Two Q2D FSs were identified in KFe2As2, occupying 12% and 17% of the first Brillouin zone.
- The cross sections of these FSs were determined to have a rounded-square shape.
- Experimental results confirmed the rounded-square FS topology through interlayer transport.
Conclusions:
- The rounded-square FS shape in KFe2As2 provides insights into the electronic structure.
- The findings suggest specific contributions of 3d orbitals to the Fermi surface.
- This study advances the understanding of electronic properties in Fe-based superconductors.
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