| Title | Neutron-Scattering Measurements of Spin Excitations in LaFeAsO and Ba(Fe0.953Co0.047)(2)As-2: Evidence for a Sharp Enhancement of Spin Fluctuations by Nematic Order |
| Publication Type | Journal Article |
| Year of Publication | 2015 |
| Authors | Zhang, Q, Fernandes, RM, Lamsal, J, Yan, JQ, Chi, SX, Tucker, GS, Pratt, DK, Lynn, JW, McCallum, RW, Canfield, PC, Lograsso, TA, Goldman, AI, Vaknin, D, McQueeney, RJ |
| Journal | Physical Review Letters |
| Volume | 114 |
| Pagination | 057001 |
| Date Published | 02 |
| Type of Article | Article |
| ISBN Number | 0031-9007 |
| Accession Number | WOS:000349249500017 |
| Keywords | anisotropy, bafe2as2, detwinned ba(fe1-xcox)(2)as-2, high-temperature superconductivity, iron arsenide superconductor, pnictides, state, transition |
| Abstract | Inelastic neutron scattering is employed to investigate the impact of electronic nematic order on the magnetic spectra of LaFeAsO and Ba(Fe0.953Co0.047)(2)As-2. These materials are ideal to study the paramagnetic-nematic state, since the nematic order, signaled by the tetragonal-to-orthorhombic transition at T-S, sets in well above the stripe antiferromagnetic ordering at T-N. We find that the temperature-dependent dynamic susceptibility displays an anomaly at T-S followed by a sharp enhancement in the spin-spin correlation length, revealing a strong feedback effect of nematic order on the low-energy magnetic spectrum. Our findings can be consistently described by a model that attributes the structural or nematic transition to magnetic fluctuations, and unveils the key role played by nematic order in promoting the long-range stripe antiferromagnetic order in iron pnictides. |
| DOI | 10.1103/PhysRevLett.114.057001 |
| Custom 1 | Correlations |
| Custom 2 | Complex States |
| Custom 3 | Novel Materials |
