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Topologically driven linear magnetoresistance in helimagnetic FeP
D J Campbell1,2, J Collini1,3, J Sławińska4,5
1Maryland Quantum Materials Center, Department of Physics, University of Maryland, College Park, MD, USA.
NPJ Quantum Information
|September 21, 2023
Summary
Iron phosphide (FeP) exhibits a massive, linear magnetoresistance when a magnetic field is applied along its c-axis. This behavior is linked to a unique semi-Dirac point in its electronic band structure.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Solid-State Physics
Background:
- Iron phosphide (FeP) belongs to the MnP-type structure family of binary pnictides.
- These materials possess a nonsymmorphic crystal symmetry, maintaining band structure features across elemental variations.
- FeP shares magnetic ordering similarities with CrAs and MnP, which exhibit pressure-induced superconductivity.
Purpose of the Study:
- Investigate the high magnetic field behavior of FeP single crystals.
- Characterize the magnetoresistance and its field dependence.
- Explore the relationship between electronic band structure and observed phenomena.
Main Methods:
- High magnetic field experiments on high-quality FeP single crystals.
- Resistance measurements up to 35 Tesla.
- Quantum oscillation frequency analysis.
- Comparison with electronic structure calculations.
Main Results:
- Resistance increases by several hundred times its zero-field value at 35 T.
- Anomalously linear field dependence of resistance observed with field along the c-axis.
- Quantum oscillations linked to a semi-Dirac point in the band structure.
- Magnetoresistance amplitude and linearity arise from distinct mechanisms.
Conclusions:
- The linear magnetoresistance in FeP is strongly dependent on magnetic field orientation.
- A semi-Dirac point, a symmetry-protected band structure feature, is identified.
- Ordered magnetism and topological band structure contribute to the observed linear magnetoresistance.
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