Low temperature specific heat of the hole-doped Ba0.6K0.4Fe2As2 single crystals
Low temperature specific heat of the hole-doped Ba0.6K0.4Fe2As2 single crystals
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空穴掺杂Ba0.6K0.4Fe2As2单晶的低温比热
DOI：
10.1103/physrevb.79.174501
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发表时间：
2008-08
影响因子：
3.7
通讯作者：
Ren, Cong
中科院分区：
文献类型：
--
作者：
Luo, Huiqian;Shan, Lei;Wen, Hai-Hu;Mu, Gang;Wang, Zhaosheng;Ren, Cong
Low temperature specific heat (SH) was measured on the FeAs-based superconducting single crystals ${\text{Ba}}_{0.6}{\text{K}}_{0.4}{\text{Fe}}_{2}{\text{As}}_{2}$. It is found that the sharp SH anomaly $\ensuremath{\Delta}C/T{\ensuremath{\mid}}_{{T}_{c}}$ in our samples reaches an unexpected high value of $98\text{ }\text{mJ}/\text{mol}\text{ }{\text{K}}^{2}$, about 1 order of magnitude larger than that of the F-doped system LnFeAsO ($\text{Ln}=\text{rare}$-earth elements), suggesting a very high normal-state quasiparticle density of states in the FeAs-122 system than in the FeAs-1111 system. Furthermore, we found that the electronic SH coefficient ${\ensuremath{\gamma}}_{e}(T)$ of ${\text{Ba}}_{0.6}{\text{K}}_{0.4}{\text{Fe}}_{2}{\text{As}}_{2}$ is weakly temperature dependent and increases almost linearly with the magnetic field in the low temperature region, which may indicate that the hole-doped FeAs-122 system contains a dominant component with a full superconducting gap, although we cannot rule out the possibility of a small component with an anisotropic or nodal gap. A detailed analysis reveals that the ${\ensuremath{\gamma}}_{e}(T)$ of ${\text{Ba}}_{0.6}{\text{K}}_{0.4}{\text{Fe}}_{2}{\text{As}}_{2}$ cannot be fitted with a single gap of $s$-wave symmetry, probably due to the multigap effect. These results indicate a clear difference between the properties of the superconducting state of the holed-doped ${\text{Ba}}_{0.6}{\text{K}}_{0.4}{\text{Fe}}_{2}{\text{As}}_{2}$ and the F-doped LnFeAsO ($\text{Ln}=\text{rare}$-earth elements) system, which we believe originated from the complex Fermi-surface structures in different systems.
Low temperature specific heat (SH) was measured on the FeAs-based superconducting single crystals ${\text{Ba}}_{0.6}{\text{K}}_{0.4}{\text{Fe}}_{2}{\text{As}}_{2}$. It is found that the sharp SH anomaly $\ensuremath{\Delta}C/T{\ensuremath{\mid}}_{{T}_{c}}$ in our samples reaches an unexpected high value of $98\text{ }\text{mJ}/\text{mol}\text{ }{\text{K}}^{2}$, about 1 order of magnitude larger than that of the F-doped system LnFeAsO ($\text{Ln}=\text{rare}$-earth elements), suggesting a very high normal-state quasiparticle density of states in the FeAs-122 system than in the FeAs-1111 system. Furthermore, we found that the electronic SH coefficient ${\ensuremath{\gamma}}_{e}(T)$ of ${\text{Ba}}_{0.6}{\text{K}}_{0.4}{\text{Fe}}_{2}{\text{As}}_{2}$ is weakly temperature dependent and increases almost linearly with the magnetic field in the low temperature region, which may indicate that the hole-doped FeAs-122 system contains a dominant component with a full superconducting gap, although we cannot rule out the possibility of a small component with an anisotropic or nodal gap. A detailed analysis reveals that the ${\ensuremath{\gamma}}_{e}(T)$ of ${\text{Ba}}_{0.6}{\text{K}}_{0.4}{\text{Fe}}_{2}{\text{As}}_{2}$ cannot be fitted with a single gap of $s$-wave symmetry, probably due to the multigap effect. These results indicate a clear difference between the properties of the superconducting state of the holed-doped ${\text{Ba}}_{0.6}{\text{K}}_{0.4}{\text{Fe}}_{2}{\text{As}}_{2}$ and the F-doped LnFeAsO ($\text{Ln}=\text{rare}$-earth elements) system, which we believe originated from the complex Fermi-surface structures in different systems.
DOI：
--
发表时间：
1963
期刊：
--
影响因子：
--
作者：
H. Rosenberg
通讯作者：
H. Rosenberg