Nematic Correlation Length in Iron-Based Superconductors Probed by Inelastic X-Ray Scattering
Nematic Correlation Length in Iron-Based Superconductors Probed by Inelastic X-Ray Scattering
Nematicity is ubiquitous in electronic phases of high-${T}_{c}$ superconductors, particularly in the Fe-based systems. We used inelastic x-ray scattering to extract the temperature-dependent nematic correlation length $\ensuremath{\xi}$ from the anomalous softening of acoustic phonon modes in FeSe, underdoped $\mathrm{Ba}({\mathrm{Fe}}_{0.97}{\mathrm{Co}}_{0.03}{)}_{2}{\mathrm{As}}_{2}$, and optimally doped $\mathrm{Ba}({\mathrm{Fe}}_{0.94}{\mathrm{Co}}_{0.06}{)}_{2}{\mathrm{As}}_{2}$. In all cases, we find that $\ensuremath{\xi}$ …