Nematic Fluctuations and Phase Transitions in LaFeAsO: a Raman Scattering Study

U. F. Kaneko; P. F. Gomes; A. F. Garcia-Flores; J. Q. Yan; T. A. Lograsso; G. E. Barberis; D. Vaknin; E. Granado

doi:10.1103/PhysRevB.96.014506

Nematic Fluctuations and Phase Transitions in LaFeAsO: a Raman Scattering Study

Strongly Correlated Electrons 2017-07-14 v2 Materials Science Superconductivity

Authors: U. F. Kaneko , P. F. Gomes , A. F. Garcia-Flores , J. Q. Yan , T. A. Lograsso , G. E. Barberis , D. Vaknin , E. Granado

View on arXiv ↗ PDF ↗ DOI ↗

Abstract

Raman scattering experiments on LaFeAsO with splitted antiferromagnetic (T_AFM = 140 K) and tetragonal-orthorhombic (T_S = 155 K) transitions show a quasi-elastic peak (QEP) in B2g symmetry (2 Fe tetragonal cell) that fades away below ~T_AFM and is ascribed to electronic nematic fluctuations. A scaling of the reported shear modulus with the T-dependence of the QEP height rather than the QEP area indicates that magnetic degrees of freedom drive the structural transition. The large separation between T_S and T_AFM in LaFeAsO compared with their coincidence in BaFe2As2 manifests itself in slower dynamics of nematic fluctuations in the former.

Keywords

nematic fluctuations phase transitions Raman scattering LaFeAsO antiferromagnetic transition tetragonal-orthorhombic transition shear modulus

Cite

@article{arxiv.1702.03774,
  title  = {Nematic Fluctuations and Phase Transitions in LaFeAsO: a Raman Scattering Study},
  author = {U. F. Kaneko and P. F. Gomes and A. F. Garcia-Flores and J. Q. Yan and T. A. Lograsso and G. E. Barberis and D. Vaknin and E. Granado},
  journal= {arXiv preprint arXiv:1702.03774},
  year   = {2017}
}

Comments

8 pages, 9 figures

Nematic Fluctuations and Phase Transitions in LaFeAsO: a Raman Scattering Study

Abstract

Keywords

Cite

Comments

Related papers