Nodal Gap in Fe-Based Layered Superconductor LaO0.9F0.1-δFeAs Probed by Specific Heat Measurements  

作　　者：牟刚 祝熙宇 方磊 单磊 任聪 闻海虎 

机构地区：[1]National Laboratory for Superconductivity, Institute of Physics and Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, PO Box 603, Beijing 100190

出　　处：《Chinese Physics Letters》2008年第6期2221-2224,共4页中国物理快报（英文版）

基　　金：Supported by the National Natural Science Foundation of China, the National Basic Research Programme of China under Grant Nos 2006CB601000 and 2006CB921802, and Chinese Academy of Sciences （ITSNEM）.

摘　　要：We report the specific heat measurements on the newly discovered Fe-based layered LaO0.9Fo0.1-δFeAs superconductor with the onset transition temperature Tc ≈ 28 K. A nonlinear magnetic field dependence of the electronic specific heat coefficient γ（ H） has been found in the low temperature limit, which is consistent with the prediction for a nodal superconductor. The maximum gap value △0 ≈ 3.4 ± 0.5 meV is derived by analysing γ（H） based on the d-wave model. We also detected the electronic specific heat difference between 9 T and 0 T in a wide temperature range, a specific heat anomaly can be clearly observed near Tc, The Debye temperature of our sample is determined to be about 315.7K. Our results suggest an unconventional mechanism for this new superconductor.We report the specific heat measurements on the newly discovered Fe-based layered LaO0.9Fo0.1-δFeAs superconductor with the onset transition temperature Tc ≈ 28 K. A nonlinear magnetic field dependence of the electronic specific heat coefficient γ（ H） has been found in the low temperature limit, which is consistent with the prediction for a nodal superconductor. The maximum gap value △0 ≈ 3.4 ± 0.5 meV is derived by analysing γ（H） based on the d-wave model. We also detected the electronic specific heat difference between 9 T and 0 T in a wide temperature range, a specific heat anomaly can be clearly observed near Tc, The Debye temperature of our sample is determined to be about 315.7K. Our results suggest an unconventional mechanism for this new superconductor.

关 键 词：supernova explosion proto-neutron star shock wave 

分 类 号：O511[理学—低温物理]