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First-Principles Study of Iron-Based Superconducting Material FeTe0.5Se0.5(PDF)

《南京师大学报（自然科学版）》[ISSN:1001-4616/CN:32-1239/N]

Issue:
2013年01期
Page:
43-47
Research Field:
物理学
Publishing date:

Info

Title:
First-Principles Study of Iron-Based Superconducting Material FeTe0.5Se0.5
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)
Keywords:
iron-based superconductor; lattice dynamics; electron-phonon interaction; first-principles
PACS:
O511+.4
DOI:
-
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.

References:

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Last Update: 2013-03-31