Field Dependence of π-Band Superconducting Gap in MgB2 Thin Films from Point-Contact Spectroscopy
HUANG Yan1, WANG Yong-Lei1, SHAN Lei1, JIA Ying1, YANG Huan1, WEN Hai-Hu1, ZHUANG Cheng-Gang2,3, LI Qi2, CUI Yi2, XI Xiao-Xing 2,4
1National Laboratory for Superconductivity, Institute of Physics and National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, PO Box 603, Beijing 1001902Department of Physics, The Pennsylvania State University, University Park, Pennsylvania 16802, USA3Department of Physics, Peking University, Beijing 1008714Department of Materials Science and Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
Field Dependence of π-Band Superconducting Gap in MgB2 Thin Films from Point-Contact Spectroscopy
1National Laboratory for Superconductivity, Institute of Physics and National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, PO Box 603, Beijing 1001902Department of Physics, The Pennsylvania State University, University Park, Pennsylvania 16802, USA3Department of Physics, Peking University, Beijing 1008714Department of Materials Science and Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
摘要We present the results of point-contact spectroscopy measurements on High-quality epitaxial MgB2 thin films with injected current along the c-axis. The temperature and field dependences of π-band properties with the field parallel to (H⊥) or perpendicular to (H|| the c-axis are investigated in detail. When a magnetic field is applied, either parallel or perpendicular to the c-axis, the density of the quasiparticle state (DOS) of the π-band proliferates quickly with increasing field, while the gap amplitude of the π-band decreases slowly, which is different from the recent theoretical calculations, showing a field dependent competition between the interband scattering and the pair-breaking effects.
Abstract：We present the results of point-contact spectroscopy measurements on High-quality epitaxial MgB2 thin films with injected current along the c-axis. The temperature and field dependences of π-band properties with the field parallel to (H⊥) or perpendicular to (H|| the c-axis are investigated in detail. When a magnetic field is applied, either parallel or perpendicular to the c-axis, the density of the quasiparticle state (DOS) of the π-band proliferates quickly with increasing field, while the gap amplitude of the π-band decreases slowly, which is different from the recent theoretical calculations, showing a field dependent competition between the interband scattering and the pair-breaking effects.
HUANG Yan;WANG Yong-Lei;SHAN Lei;JIA Ying;YANG Huan;WEN Hai-Hu;ZHUANG Cheng-Gang;LI Qi;CUI Yi; XI Xiao-Xing;. Field Dependence of π-Band Superconducting Gap in MgB2 Thin Films from Point-Contact Spectroscopy[J]. 中国物理快报, 2008, 25(6): 2228-2231.
HUANG Yan, WANG Yong-Lei, SHAN Lei, JIA Ying, YANG Huan, WEN Hai-Hu, ZHUANG Cheng-Gang, LI Qi, CUI Yi, XI Xiao-Xing,. Field Dependence of π-Band Superconducting Gap in MgB2 Thin Films from Point-Contact Spectroscopy. Chin. Phys. Lett., 2008, 25(6): 2228-2231.
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2008, Vol. 25 
