Physics – Condensed Matter – Strongly Correlated Electrons
Scientific paper
2011-10-26
Physics
Condensed Matter
Strongly Correlated Electrons
5 pages, 4 figures, Typos corrected
Scientific paper
We study the influence of quantum fluctuations on the electron self energy in the normal state of iron-pnictide superconductors using a five orbital tight binding model with generalized Hubbard on-site interactions. Within a one-loop treatment, we find that an overdamped collective mode develops at low frequency in channels associated with quasi-1D $d_{xz}$ and $d_{yz}$ bands. When the critical point for the $C_4$ symmetry broken phase (structural phase transition) is approached, the overdamped collective modes soften, and acquire increased spectral weight, resulting in non-Fermi liquid behavior at the Fermi surface characterized by the frequency dependence of the imaginary part of electron self energy of the form $\omega^\lambda$, $0<\lambda<1$. We argue that this non-Fermi liquid behavior is responsible for the recently observed zero-bias enhancement in the tunneling signal in quantum point contact spectroscopy. A key experimental test of this proposal is the absence of the non-Fermi liquid behaviour in the hole-doped materials. Our result suggests that quantum criticality plays an important role in understanding the normal state properties of iron-pnictide superconductors.
Lee Wei-Cheng
Phillips Philip W.
No associations
LandOfFree
Non-Fermi Liquid due to Orbital Fluctuations in Iron Pnictide Superconductors does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Non-Fermi Liquid due to Orbital Fluctuations in Iron Pnictide Superconductors, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Non-Fermi Liquid due to Orbital Fluctuations in Iron Pnictide Superconductors will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-374584