[1]李 健,茅伟华,黄桂芹.铁基超导材料FeTe0.5Se0.5的第一性原理研究[J].南京师大学报(自然科学版),2013,36(01):43-47.
　Li Jian,Mao Weihua,Huang Guiqin.First-Principles Study of Iron-Based Superconducting Material FeTe0.5Se0.5[J].Journal of Nanjing Normal University(Natural Science Edition),2013,36(01):43-47.
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铁基超导材料FeTe0.5Se0.5的第一性原理研究()
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《南京师大学报（自然科学版）》[ISSN:1001-4616/CN:32-1239/N]

卷:
第36卷
期数:
2013年01期
页码:
43-47
栏目:
物理学
出版日期:
2013-03-31

文章信息/Info

Title:
First-Principles Study of Iron-Based Superconducting Material FeTe0.5Se0.5
作者:
李 健1; 茅伟华2; 黄桂芹1
(1.南京师范大学物理科学与技术学院,江苏 南京 210023) (2.江苏省吴江市青云实验中学,江苏 吴江 215235)
Author(s):
Li Jian1; Mao Weihua2; Huang Guiqin1
(1.School of Physics and Technology,Nanjing Normal University,Nanjing 210023,China) (2.Qingyun Experimental Middle School,Wujiang 215235,China)
关键词:
铁基超导; 晶格动力学; 电声子相互作用; 第一性原理
Keywords:
iron-based superconductor; lattice dynamics; electron-phonon interaction; first-principles
分类号:
O511+.4
摘要:
采用第一性原理计算了FeTe0.5Se0.5在两种不同结构模型下的电子结构、晶格动力学以及电声子相互作用.结果表明:用两种结构模型计算得到的电子结构大致相同,费米面附近的态密度主要来自Fe d电子的贡献.对两种模型我们根据不可约表示分析了Γ点的光学模频率,并给出了声子谱及声子态密度.用模型1和模型2计算得到的电声子耦合常数λ分别为0.20和0.22,都非常弱,无法解释实验上较高的超导转变温度.因此,超导材料FeTe0.5Se0.5和其他的铁基超导材料一样,都不属于常规的电声子耦合超导材料.
Abstract:
The electronic structure,lattice dynamics and electron-phonon interaction of FeTe0.5Se0.5 in two different structural models are investigated by using the first-principles.The results show that the electronic structures of the two structural models are similar to each other,and the electronic density of states near the Fermi level comes mainly from Fe d electrons.For both two models,we analyze the optical modes at the Γ point based on irreducible representation,and give the phonon spectra and the phonon density of the states.The electron-phonon coupling coefficients λ calculated by model 1 and model 2 are 0.20 and 0.22,respectively,which are both too small to explain the high superconducting transition temperature discovered in experiment.Therefore,we think that superconducting material FeTe0.5Se0.5 doesn’t belong to the conventional electron-phonon coupling mechanism,which is similar to the other Fe-based superconducting materials.

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备注/Memo

备注/Memo:
收稿日期:2012-06-15.
基金项目:国家自然科学基金(10947005).
通讯联系人:李健,硕士研究生,研究方向:凝聚态物理.E-mail:lijian2006400457@126.com
更新日期/Last Update: 2013-03-31