Abstract

High-temperature superconductivity in the Fe-based materials emerges when the antiferromagnetism of the parent compounds is suppressed by either doping or pressure. Closely connected to the antiferromagnetic state are entangled orbital, lattice, and nematic degrees of freedom, and one of the major goals in this field has been to determine the hierarchy of these interactions. Here we present the direct measurements and the calculations of the in-plane uniform magnetic susceptibility anisotropy of BaFe2As2, which help in determining the above hierarchy. The magnetization measurements are made possible by utilizing a simple method for applying a large symmetry-breaking strain, based on differential thermal expansion. In strong contrast to the large resistivity anisotropy above the antiferromagnetic transition at TN, the anisotropy of the in-plane magnetic susceptibility develops largely below TN. Our results imply that lattice and orbital degrees of freedom play a subdominant role in these materials.

Highlights

  • High-temperature superconductivity in the Fe-based materials emerges when the antiferromagnetism of the parent compounds is suppressed by either doping or pressure

  • Many optimally doped Fe-based materials appear to be close to a putative nematic quantum critical point[28], and recent theoretical works suggest that electronic nematic fluctuations may provide a boost to superconductivity in various channels[37]

  • Samples were glued onto a glass-fiberreinforced plastic (GFRP) substrate with the crystal’s tetragonal

Read more

Summary

Introduction

High-temperature superconductivity in the Fe-based materials emerges when the antiferromagnetism of the parent compounds is suppressed by either doping or pressure. TN, which is driving has raised the question of these transitions[8,9,10,11], or whether whether orbital degrees of freedom need to be considered[12,13,14,15] This issue is pressing for FeSe, which has no long-range magnetic order down to the lowest temperature at ambient pressure but exhibits a similar orthorhombic distortion as the other Fe-based materials[16,17,18]. This non-magnetic and orthorhombic phase has been coined “electronic nematic”[10, 19]. We study the interplay between lattice, orbital, magnetic, and nematic degrees of freedom in the parent compound

Methods
Results
Conclusion

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.