A Close Correlation between the Logarithmic Quasiparticle Energy and Superconducting Transition Temperatures of Iron-Pnictide Compounds

作者：Misawa Setsuo^*

来源：Journal of the Physical Society of Japan, 2014, 83(5): 054701.

DOI：10.7566/JPSJ.83.054701

One of difficult problems in iron-based superconductors (normal state) is that the temperature (T) variation of the electrical resistivity deviates from the T-2 law. Here we resolve this problem by assuming that the systems are truly 3-dimensional (3D) Fermi liquids. Because of interactions and the presence of Fermi surface, the quasiparticle energy measured from the Fermi surface, epsilon, contains, as a function of momentum p with the Fermi momentum p0, a (p - p0)(3) In vertical bar p - p0 vertical bar term which produces a epsilon(2) In vertical bar epsilon vertical bar term in the density-of-states function. This term gives rise to a T-2 In T term in the electronic specific heat coefficient, impurity resistivity and total resistivity. Spin-antisymmetric shortwavelength density fluctuations creates a T-2 n T variation of the magnetic susceptibility. We show that existing experimental data obey universally this T-2 In T law. Through this analysis we find a close correlation between the magnitude of the epsilon(2) In vertical bar epsilon vertical bar term and superconducting transition temperatures; this suggests that, around 3D Fermi surfaces, the interactions which give rise to the logarithmic energy are important for the occurrence of superconductivity.

• 出版日期2014-5