1. Specific heat of iron-based high-Tc superconductors
Li Ding (No ),1 J. K. Dong,1 T. Wu,2 R. H. Liu,2 G Wu2, X. H. Chen,2 and S. Y. Li1
1Department of Physics and Laboratory of Advanced Materials,, Fudan University, Shanghai , China
2Hefei National Laboratory for Physical Science at Microscale and Department of Physics,
University of Science and Technology of China, Hefei, Anhui , China
Summary
A specific heat jump was observed at 130K for the x = 0 sample, corresponding to the structural or SDW transition. However, it disappears in x = 0.05 sample, indicating the suppression of the SDW order and structural distortion by electron doping in this system
A clear specific heat anomaly can be seen near Tc for superconducting SmO1−xFxFeAs samples, while it has been absent in LaO1−xFxFeAs. This result suggests higher superfluid density in SmO1−xFxFeAs.
A clear peak of C/T can be seen at Tc = 36K for Ba0.5K0.5Fe2As2. No obvious anomaly is found below Tc = 18K for Ca0.5Na0.5Fe2As2
The electronic specific heat coefficients of these compounds were obtained.
Main References
[1] X. H. Chen, T. Wu, G. Wu, R. H. Liu, H. Chen, D. F. Fang, Nature 453, (2008).
[2] R. H. Liu, G. Wu, T. Wu, D. F. Fang, H. Chen, S. Y. Li, K. Liu, Y. L. Xie, X. F. Wang, R. L. Yang, L. Ding, C. He, D. L. Feng, X. H. Chen, Phys. Rev. B 101, (2008).
[3] J. Dong, H. J. Zhang, G. Xu, Z. Li, G. Li, W. Z. Hu, D. Wu, G. F. Chen, X. Dai, J. L. Luo, Z. Fang, N. L. Wang, Europhysics Letters 83, (2008).
[4] Rotter M, Tegel M, Johrendt D, Schellenberg I, Hermes W and Pottgen R Phys. Rev. B (2008).
Published Papers: L. Ding, et al, Phys. Rev. B 77, (R) (2008) J. K. Dong, L. Ding, et al, New Journal of Physics (2008)